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The aquifer at Phosphate Hill, north-west Queensland, presents special management challenges. The site contains a phosphate rock mine, fertilizer plant and camp. All of the site water is provided by the Duchess Embayment Aquifer, located within the Burke River Outlier of the Georgina Basin. The Duchess Embayment is a triangular shaped, Cambrian marine sedimentary basin consisting of siliceous and calcareous phosphorites, shales, siltstones and sandstones. It is fault-bounded on all sides and has a regional dip of 5¦E. The aquifer is largely confined to the siliceous facies of the Beetle Creek Formation. It has a very flat potentiometric surface and an average thickness of 45 m with confining beds above and below. The siliceous facies derives from weathering of the calcareous phase and is highly transmissive while the calcareous zone itself contains less water and is dependent upon interconnecting fractures for its permeability. Recharge appears to occur where the siliceous facies crops out around the edges of, and within, the Embayment. Aquifer management issues revolve around two points: successful dewatering of the orebody for mining; and efficient management to maintain water quality and ensure supply over the predicted 30-year life of the project. Current operations are extracting water at levels much below that originally estimated. This is having a detrimental effect on mine dewatering with the SWL lowering at a rate slower than anticipated. As a result, ore parcels are now beginning to intersect the water table, providing a major constraint to the mining plan. The aquifer drawdown cone is extensive and very flat so to keep the water table at an appropriate level for mining the management plan will include more aggressive dewatering to lower the level of the entire aquifer. The additional water will either be disposed of downstream or stored in a holding dam or via the use of artificial storage and recharge. Water resource management will also need to maintain the current quality. About 37 per cent of the water currently extracted forms the low chloride supply required by the ammonia plant and the power station. This ratio is expected to remain applicable under any future operating conditions but the low chloride resource is restricted so will require prudent management to enable the supply to continue. At current usage rates aquifer recharge versus use will need careful monitoring to ensure that the resource remains viable in the long-term.

Jan 1, 2003

In the geologically prospective nations which rim the Pacific Ocean, mineral deposits offer great potential to create wealth for social and economic development. The paper first examines the geological and economic attributes of potential mineral wealth based on current outlook assessment of all significant base metal deposits discovered to 1988 in two Pacific Rim nations - Australia and Canada. The variability of mineral wealth among the economic deposits evaluated and the major contribution of the few world-class discoveries to total mineral wealth are highlighted. Then, the essential but too often neglected linkage between the makeup of potential wealth and its actual realization is analyzed. The impact of taxation and the role of exploration are crucial in this regard. Finally, the ingredients of exploration success, prerequisites for realizing the mineral wealth of nations, are examined.

Jan 1, 1995

Interest in the sampling of refined copper cathodes has heightened over the last ten years. This has followed the increasing importance of cathodes as the principle trading form for metallic copper. It has also been given impetus by recent trends for quality certification of manufacturing inputs, specifically the AS3900 and IS09000 series of standards.

Jan 1, 1976

Geostatistical conditional simulation is a method to assess variability and risk in mineral deposits and the tool has wide potential applications in the iron ore industry. Correct reproduction of multivariate relationships is important in iron ore simulation, especially between Fe and impurities such as Al2O3, SiO2 and P. The turning bands simulation method, using a full model of coregionalisation for multiple attributes, is the main multivariate conditional simulation algorithm used in the Western Australian iron ore industry. This paper discusses the results of a more recent approach using minimum/maximum autocorrelation factors (MAF) to transform and decorrelate the multivariate data prior to independent sequential Gaussian simulation (SGS). MAF-SGS results are compared to those of the turning bands approach in the Yandicoogina channel iron ore deposit (CID), and both methods performed well in simulating Fe, SiO2, Al2O3 and P distributions. Extensive checking of simulations showed that both approaches could reproduce multivariate statistics and spatial continuity of the original conditioning data. Both approaches reproduced the histograms and variography of input sample composites. While the MAF-SGS approach requires additional transformations when compared with the single normal scores transformation required for the turning bands method, MAF requires only that the direct semivariograms be modelled. In contrast, using turning bands with multiple attributes requires modelling a full linear model of coregionalisation, which can be difficult to model because of the need to ensure the model is positive semi-definite. Turning bands may be preferred if there are a modest number of correlated variables allowing construction of a linear model of coregionalisation that adequately models the multivariate behaviour. MAF-SGS is preferable for larger numbers of correlated variables. Both MAF-SGS and turning bands methods performed well in conditional simulation of correlated variables at Yandicoogina.

Jan 1, 2007

By Hohnen CA, Limerick JM, Hall DRT

An uniquely-designed flash furnace for smelting of nickel concentrate and for the recovering of metal values from the slag generated has been in successful use for nearly six years. Within the last eighteen months the ability of the furnace to treat slag arising from converting operations without significant reduction in capacity has also been successfully demonstrated. Previously, converter slag had been treated separately in an electric furnace. The salient features of smelter developments are outlined and slag chemistry is discussed. The low cost method for the introduction of coal to partially replace light fuel oil is reviewed and total energy requirements evaluated.

Jan 1, 1984

By H Zahiri

Utilisation of the InSAR technique for monitoring of subsidence in mining areas, employing open pit and underground mining methods, has large potential due to sensitivity and safety issues associated with usage of the classical surveying techniques. InSAR can also be very competitive concerning the cost of provided results. However, there are a few issues that may significantly limit InSAR applicability for subsidence monitoring in mining areas. The altered terrain topography, involving steep slopes and deep pits, may lead to the layover of radar signal for specific satellite and pit geometry. Also, the highly dynamic character of subsidence induced by mining, especially using mass mining methods, may lead to issues such as apparent heave and ambiguous results. In this paper the authors analyse the above-mentioned issues and demonstrate how InSAR technology was applied, as a supporting system, to monitor large scale and highly dynamic subsidence for a real case study in Western Australia.

Jan 1, 2008

By L Soares, W T. Hennies, F Fujimur

Barra Bonita reservoir, located in the Sao Paulo State, Brazil, has been mainly used for local navigation and electricity generation to supply a prosper region in the country. Sand mining activities in that area have an important social and economic meaning for the local community. In this reservoir there are several sand mines that produce around 45 000 m3 of sand a month. These deposits were rich in material used as concrete aggregate in the civil construction. However, nowadays a significant increase in the demand of gravel can be observed, representing a serious productive problem. This material hasnÆt been well accepted by the market and, through the years, it was disposed at open sky in piles as waste deposits. This deposits have caused environmental problems like visual impact, reduction of free spaces outside and inside the mine, source of material to erosion and sedimentation processes in lower areas, flooding as a result of the filling up process in the drainage system, among others. For a lack of an appropriate technological characterisation, this material have been mainly used to pavement internal and external areas in the mine, with lower cost associated. With the purpose of evaluate the usefulness of this material in the conventional concrete, there were conducted several tests in the disposed residue including petrographical, physical, and chemical characterisation. The petrographical analysis and the preliminary results of the study showed that the material reacts with the alkalis that are present in the conventional cement (CP-II-E-32). In order to make the application technical and economically possible a research was developed seeking forms to correct this characteristic by adding special cements with high pozzolana content. The results of the technological, physical and chemical characterisation of the products indicated the technical viability of the use of that material. The study also allowed projecting environmental improvements resulting in the elimination of the waste piles.

Jan 1, 2003

The Olympic Dam mining operation is some 520 kilometres NNW of Adelaide on the Roxby Downs Pastoral lease. The deposit containing copper, uranium, gold and silver was discovered in 1975 by Western Mining Corporation (WMC). A joint venture was formed in mid-1979 between WMC (51 per cent) and British Petroleum (BP, 49 per cent) for the development and exploitation of the deposit. WMC assumed 100 per cent ownership after acquiring BP's share in early-1993. Ore is won from a highly mechanised underground mining operation and processed to refined products. Current annual output from the mining of 3.0 Mt of ore is approximately 83 500 t of refined copper, 1400 t of uranium oxide, 750 kg of gold and 12 000 kg of silver. Conventional long hole, open stoping techniques are used to extract the production ore. Since stope production began in April 1988, full surveys and appraisals of stopes have been carried out to evaluate the integrity of the design and blasting techniques. This evaluation included the determination of the degree of dilution or non break that had occurred. Performance information also made it possible to re-design any adjacent stopes to retrieve remaining ore and conversely, avoid the chances of targeting backfilled material in the future. Performing stope surveys proved not only to be a time-consuming process but one fraught with access and line-of-sight problems. Occasionally it was not possible to obtain any stope survey data, and as was often the case with the mine pass system, rarely. In 1992 the sudden failure of the pillar between the fine ore and mullock passes and the subsequent delays to production, emphasised the need to effectively monitor pass wear. Initial information regarding the development of the Cavity Measurement System (CMS) prototype (Figure 1) indicated that it had the potential to solve these problems by the introduction of a remote scanning device into a cavity. Following a great deal of investigation, Olympic Dam Operations purchased the first CMS in Australia. This paper discusses its application for all underground void surveys and the procedures developed to manage both field and office requirements.

Jan 1, 1995

A study is presented of the theoretically possible initiation systems for outbursts and the subsequent propagation mechanism.Previous occurrences of outbursts and their correlation to the theoretical system are described. An estimation of the energy release from two energy sources, gas strain energy and rock/coal strain energy, is presented and the relative importance of each source in the severity of outbursts. Summary: The description of mechanisms of outbursting follows the examination of these phenomena at Collinsville in Bowen No. 2 mine and at Leichhardt Colliery, Blackwater. Quantitative material contained in the paper refers to Leichhardt Colliery, Blackwater. Clearly from the work carried out to date gas release has a major part to play in the out- bursting at both of these collieries. In the case of the December 1 1978 outburst at Leichhardt Colliery energy release estimates place gas strain energy release contributing eight times the energy of that from rock/coal strain energy. Even the normal outbursts at Leichhardt Colliery appear to show this trend. Estimates of energy released are for comparative purposes between gas and rock strain energy and the values obtained may be regarded as approximate.

Jan 1, 1980

Based on twenty years of experiences of applying computers in mine water engineering in Hungary, a program package was developed for home utilization and for other users abroad as well. This program package has been adapted to the CAD System of Coal Mining of COMECON countries. The main features of the "mine water subsystem" in the CAD System of Coal Mining and short descriptions of the key programs of the package are presented in this paper. Foreword The serious water problems of Hungarian mining pressed and/or stimulated its professionals to apply computers for supporting their problem-solutions. The first trials of these computer applications in mine water engineering were dated from the sixties. Owing to its twenty years of experiences in computer appli- cations in mine water engineering the Central Institute for the Development of Mining in Hungary was requested to work out the "Subsystem of Mine Water" for the Computer Aided Design System ('CAD) of Coal Mines in COMECON countries. This paper gives a brief presentation on the main features of this "subsystem"with reference to significant components.

Jan 1, 1988

A BRIEF account of the water-power potentialities of Tasmania is given, together with possible applications of the power commercially. A short history of the Waddamana development is then given, and the main works are described.WATER POWER POTENTIALITIESTasmania is an island of approximately 24,500 sq. miles area (exclusive of small islands). An area of 12,000 sq. miles is at an elevation of over 1000 ft. above sea-level, and of 2300 sq. miles at over 3000 ft. above sea-level. Average annual rainfall varies from' over 140 in. on West Coast to 20 in. on East Coast, and for the whole island averages 48.5 in. The total water-power available, based on conservative figures for run off and efficiency, is 6,000,000 b.h.p. Only a small percentage of this total will, under present conditions, and under likely conditions in the immediate future, be capable of being developed commercially.An extensive hydro-metric and water-power survey is at present being carried out in order to collect information concerning the most promising water-power schemes. Already 400,000 b.h.p. has been located in different proposals, and there is still a large area of very likely country along the West Coast which has not been investigated yet. Tasmania thus has very vast power potentialities, which, combined with good ports and communications and wonderful mineral and timber resources, should augur well for the establishment of the great key industries, particularly chemical and metallurgical.

Jan 1, 1923

By M Kilburn, A Edenton, M Adam, A Dehghan-Manshadi, R Smyth, L Lu

The blast furnace is a counter current reactor. The counter current principle of the furnace makes it very efficient in transferring the heat and mass required to drive the reduction reactions inside the furnace. However, this does impose a stringent requirement on the permeability of burden material in the furnace. Lump ore is one of the key ferrous feeds used in the blast furnace ironmaking process, often accounting for ten to 20 per cent of the blast furnace ferrous burden. As the lump ore descends through the blast furnace, it is dried, heated and reduced by the ascending hot reducing gas. To ensure good furnace permeability, generation of fines from burden materials including lump ore due to mechanical, thermal and chemical processes needs to be minimised. Unlike sinter and pellets, lump ore is subject to thermal degradation. To assess this behaviour of lump, the ISO decrepitation test (ISO 8371, 2007) is often conducted, and the result is calculated as a decrepitation index (DI). However, the DI values obtained from the existing ISO decrepitation test vary considerably between test portions and between laboratories, which makes meaningful comparison very difficult. In order to identify the sources responsible for the unacceptable repeatability, the effect of various testing conditions, such as particle size, heating rate, sample preparation and loading method, on the mean DI value was studied. The mechanisms contributing to thermal degradation in the top of the blast furnace and during the standardised decrepitation test are also discussed.CITATION:Lu, L, Kilburn, M, Dehghan-Manshadi, A, Adam, M, Edenton, A and Smyth, R, 2013. Thermal degradation of lump ore in the top shaft of blast furnaces, in Proceedings Iron Ore 2013 , pp 421-426 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By Leahy GJ, Wright DJ, Player RI

The operation of a one tonne submerged combustion pilot plant for the recovery of copper from anode furnace and converter slags is described and the effects of variables discussed. Using coal as reductant, copper levels of anode furnace slag were lowered to 1% or less, with batch times of approximately 120 minutes. Fluxing with limestone was required to produce a fluid slag at temperatures of 1200 - 1300¦C. For converter slags, reduction to 0.5% Cu or less was achieved in batch times of 35 minutes. The chemistry of the pyrometallurg- ical recovery of copper is briefly reviewed in relation.to copper recovery methods.

Jan 1, 1978

By Goto T, Sato K, Mori N

A field investigation by making use of the seismic method has been carried out in order to comprehend the mechanism of rockburst and gas outburst and their predictive measures. The seismometers were so arranged both on the surface and underground as to enclose a mining panel. Seismic signals detected by the array were recorded and processed by the 32-kwords computer system. At present the system is available for analysing the source location and Richter's scale of each event and for visualizing the distribution of seismic foci and released energy at any mining stage. The magnitude distribution of events can be regarded as a comparable index of the seismic activities among mining panels. An analysis of the spatial density distribution of seismic energy in the mining panel can be useful to distinguish a highly stressed zone from stress released areas. The energy released curve or the rate of energy release determined from seismic data is also a good indication of the seismicity.

Jan 1, 1980

By R Williams, P Godwin

In a time of changing rainfall patterns and in the light of recent tailings dam failures, there is closer environmental scrutiny for proposed tailings dam construction or expansion. Therefore the elimination of the traditional tailings dam could provide both environmental and cost benefits to an operation. One method to dewater tails is using pressure filtration to achieve lower moistures than what is currently available using other dewatering technologies. Further benefits include a higher rate of filtrate recovery, reuse of waste material and the potential for dry stacking of the filtered tailings cake, thereby minimising both risk and cost. This paper chronicles the replacement of two existing belt filter presses with a single McLanahan recessed plate filter press to dewater a tailings stream at a Bacchus Marsh site. It covers the slurry testing, equipment selection, installation, commissioning and operation of the filter press to achieve the following objectives:• removing the current tailings dam and slimes cells from the existing process to minimise failure risk and reduce the cost of a dam upgrade, as well as operational and maintenance costs• free up the surface area which was previously occupied by tailings dams and slimes cells• recover additional water to be returned to the process• reduce flocculent usage• reduce truck movements and handling.The project’s owner also expects to reduce carbon emissions by over 3000 t over the lifetime of operation as well as substantially reducing operating expenditure. By recognising the carbon reduction benefits, the project owner was able to successfully achieve partial funding through the Voluntary Waste Industry Protocol.An unanticipated, but as yet unquantifiable, bonus for the project was to seek an offtake agreement for the tailings thereby allowing the tailings to be considered a valuable source of beneficiated clay suitable for the construction industry.CITATION:Godwin, P and Williams, R, 2017. Pressure filtered tailings – environmental and cost benefits, in Proceedings MetPlant 2017, pp 324–334 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

One of primary causes of poor blast performance is the improper relief of explosive energy. Under or over-confined blasts modify the explosiveÆs path of least resistance, which changes where and when the explosive energy is applied resulting in less than optimum blast performance. During the research for this paper the overbreak characteristics of five full-scale blasts were quantified using high speed cinematography and borehole cameras. The effectiveness of various overbreak control methods was also evaluated to guide design refinement. The results of this research along with general recommendations for reducing excessive damage are included with this paper.

Jan 1, 1999

An established method exists for the computation of rope lifetimes for shaft hoisting applications in the mining industry. In an earlier study, during the 1990s, an initial comparison of the calculated and actual rope life for various types of hoisting plants showed reasonably good correlation. In the meantime the calculation method has been developed further. The rotation behaviour of the rope during hoisting and the effects of multilayer spooling on drums are now considered in the assessment of expected rope lifetimes. The ability to determine an estimate of rope life in advance is particularly useful for mining companies. Such analysis allows them to predict the effects of rope choice in their particular application and thereby reduce the total cost of rope ownership. Such calculation techniques also allow designers of winding plants to identify aspects of the hoisting configuration that may negatively affect rope life. Often small (low-cost) changes, like increasing the diameter of head sheaves, can result in considerable improvements in rope performance. This paper describes the extended lifetime calculation method and gives further examples of the comparison between actual and calculated rope lives for operational double-drum mine hoists.

Jan 1, 2005

By Glastonbury J. R

The kinetics of the direct chlorination of, zircon in the presence of carbon was studied at temperatures between 9000C and 12000 C. From the experimental data it is prop- osed that the most likely mechanism for metal oxide (MeO2) chlorination is as follows: At I Surfaceon zMeO2+ZMeCl - MeOC12 (1) At Carbon MeOC12+C+Cl MeC14+CO (2) Surface It.is envisaged that this type of mechan- ism would occur for both the zirconium and, silicon. constituents of the ore. In the above mechanism; the surface re- actions appear to be fast and not rate controll- ing. In a carbon surface deficient bed the diff- usion of oxychloride intermediate through the boundary layer to the carbon surface becomes the rate controlling step. In a zircon surface deficient bed the diffusion of oxychloride away from the zircon surface controls the reaction. This postulated mechanism can be used to ex-, plain the observed experimental effects.

Jan 1, 1973

A simple method of designing effective fill drainage systems for slurry backfill is presented. By using the proposed method, it is easy to calculate and predict the expected fill drainage rates or to provide additional drainage systems to accelerate the fill drainage. The fundamentals of hydraulic fill and an efficient method to determine its permeability is also explained. The safety in hydraulic filling and bulkhead stability depends totally on achieving effective drainage regime for the fill. This paper provides the basis for creating such efficient drainage regimes. The recent fatal fill bulkhead failures in Australia were the result of poor drainage from the respective fill masses, and therefore it is more important to provide suitable drainage arrangements to continue using hydraulic fill to the benefit of the mining industry. At present there is no procedure available to mine operators to estimate the expected bulkhead pressures to design a satisfactory bulkhead. Some mines are constructing bulkheads after their initial investigations carried out years ago. Other mines have simply borrowed the ideas from the pioneer mines and using in their areas. It is high time that we develop a rational approach to estimate the expected bulkhead pressures for the design of bulkheads. We need a simple model that could be understood and used by the mine operators on a day-to-day basis. This paper also presents a model to predict the bulkhead pressures for designing safe bulkheads.

Jan 1, 2002

The implementation of a process information management system (PIMS) is to provide a single online, real-time information system. This system provides a unique and completely open view for everyone, based on the key business drivers. It is structured around the three key concepts: process, maintenance and stocks. It combines numerous applications and provides accessibility to common tools and reports, through a web-based user interface, for every one from the floor operator to the General Manager. This æunique and commonÆ view displays raw, online process information that provides a quick health check of the operation at a glance, highlighting areas that require further investigation. The system is based on a hierarchical system of views, from the overview of the whole plant flow sheet to the more detailed operational shop view. It provides a synthetic view between continuous and batch operations, enabling the tracking of each batch produced. The batch view displays the critical batch components, and a comparison with each component of an ideal batch. This enables detailed analysis of each batch to identify areas of improvement. The information system will consist of an online reconciliation of stocks and flow data. This enables focus on the recovery of each process unit on a regular basis. This paper discusses the design strategy for the Process Information Management System, to ensure a unique and open view on the key business drivers is achieved and implemented successfully.

Jan 1, 2005