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Comminution of solids is surely one of the oldest technologies which even in this day and age of DNAs, chips and space exploration continues to challenge our scientific acumen and engineering ingenuity. In essence, this challenge is two-fold. One, as much as three to four per cent of all electric power generated world-wide is consumed in crushing and grinding primarily because the utilisation of energy is woefully poor. Studies have shown that the efficiency of mechanical size reduction processes is of the order of 1.5 to 12 per cent only (Schoenert 1986). Two, with the grinding technologies available to us, we have, at best, inadequate and, at worst, almost negligible control over the shape of the comminuted particles, size dispersion of the ground mass, and the sharpness of mineral liberation. Low energy efficiency and lack of control in the sense mentioned above have far-reaching implications for resource conservation, performance of down stream unit operations, and damage to the environment. Our problem is in fact central to the mineral-energy resources triangle shown in Figure 1 which depicts the close interrelationships among mineral resources which are becoming poorer in content and more complex in mineralogy each day, energy resources which are depleting rapidly without any viable alternate on the horizon, and environmental concerns which can no longer be ignored. It is evident that any improvement in the efficiency of the comminution process impacts directly on the control of environmental damage, conservation of energy and the economics of the operation. These concerns have special relevance for the processing of non-ferrous ores.

Jan 1, 1992

The geology of an area in north-western New South Wales, bounded by the South Australian and Queensland borders, latitude 32° S. and longitude 14° E. is discussed.The area involved includes sixteen 1:250,000 standard military sheets and covers approximately 96,000 sq. miles.The geology of the Willyama Complex is not dealt with but a small area of metasediments previously included in this unit is separated and a possible correlation with Precambrian to the east is suggested. Torrowangee Group sediments are described and the problem of nomenclature using a glacial implication is raised.Nine areas of proven Lower Palaeozoic sediments are considered and their relationship to the boundaries of the Bancannia Trough outlined. It is possible that some exposures not yet substantiated by fossil evidence may prove to be Lower Palaeozoic rather than Precambrian in age.The sediments of the Lachlan Geosyncline in the area of the Cobar massif are described and new concepts on the age and distribution of some of the established stratigraphic units are introduced. The absence of rocks of Middle Silurian age probably indicates the time of a major orogeny in this area.Lithology, thickness, and distribution of the Upper Devonian sediments is considered and some of the more recently found fish plate localities are listed.Mesozoic sediments occur in isolated areas of Lower Jurassic age and in the Great Australian (Artesian) Basin. A four-fold subdivision of sediments of the basin has been possible in some areas but lack of sub-surface information at present, precludes the possibility of correlation with the type sections in Queensland.Units in the Cainozoic are subdivided and a five fold subdivision of the Quaternary, at present being used throughout western New South Wales, is described.

Jan 1, 1969

By J Parmenter

Issues around water û its quality, use, availability and environmental value û can be a major point of tension between mineral projects and local communities. Failure to manage these issues appropriately can jeopardise the obtaining of regulatory approvals for new projects and place at risk the æsocial licence to operateÆ of existing operations. Conversely, there may also be significant opportunities for companies to engage constructively with communities over water issues and to make a positive contribution to the sustainable development of these communities. Using case studies, this paper will explore the various types of social risks and opportunities associated with water and mineral resource development and identify key learnings relating to the management of these issues.

Jan 1, 2006

The long term viability of a mining company is dependent on the success of its capital investments. Due to the specialised nature of the design, engineering and construction of large projects the management is often contracted to an outside organisation. This paper is a review of the phases of the relationship between Client and Contractor. A rationale is developed upon which the selection of a Contractor can be made. Subsequently, the key aspects of the Client/Contractor relationship are reviewed with reference to completing the project on time within budget. The aspects discussed include Contractor management systems, qualifications of key personnel, definition of scope of work, industrial relations, project control and Contractor remuneration.

Jan 1, 1983

Modern, research-based approaches to mineral exploration are essential to the future maintenance of the mineral industry. These need to fully utilise the rapidly expanding growth of understanding of the evolution of the earth's crust, and be properly integrated with advances in understanding of chemical and physical processes involved in ore formation. BMR has a major role to play in supporting the growth and utilisation of this research base, as well as maintaining the national geological and geophysical bases which are essential both to tactical and strategic interests of Australia and of its mineral industry. The objective development of data-process modelling is one target of such strategic research based on a more integrated approach to research by BMR, mineral companies, CSIRO and the universities with emphasis given to promoting positive feedback during research activities. Examples of the success of strategic research in Australia and overseas are noted in the Text.

Jan 1, 1986

Mining companies in Australia have grown in size and complexity over the past 20 years. The same period has seen exten- sive changes in the operating environment, with greater competition and intensified in- dustrial and social pressures placing new demands 'on mining activity. The new condi- tions require a management approach that emphasises strategic planning rather than operational efficiency. Strategic management evolves through four distinct phases, namely, financial planning, forecast-based planning, externally oriented planning and 'true' stra- tegic management. The most difficult transi- tion to make is from Phase 2 (forecast-based planning) to Phase 3 (externally oriented plan- ning) since management is often too involved in operations to find time to develop and main- tain a strategic orientation towards the mar- ket and competitors. Reorganisation of re- sponsibility for operations and improved op- erational processes enable management to concentrate on external opportunities.

Jan 1, 1980

The estimate of an ore reserve is a vital statement made about a mineral occurrence by an evaluator. It is important that such a statement communicate reality to all groups involved in a mining project, be they technical, financial, company directors, Stock Exchanges or the public. Ore reserve statements should state both resources and recoverable ore reserves. Resources may be important in very long term considerations, (because mining, metallurgical technology and economics change with time) but recoverable reserves are todays reality. The important factors contributing to recoverable reserves (in a general sense) are geology, mining method (and its impact on dilution and ore loss), metallurgical recovery, costs and commodity prices. These all need to be reflected in the ore reserve statement. In this paper recoverable ore reserve concepts across a wide range of orebodies are considered and discussed with respect to geology, mining method and ore reserve calculation procedures.

Jan 1, 1987

The Energy Authority of NSW has wide powers and responsibilities conferred by its Act which are pertinent to the State's coal industry and its development into the next century. With respect to coal, the broad objective is to maximise the benefits to NSW and its people derived from the State's coal resources. The initial focus of the Authority's coal-related activities in the late 70's and early 80's was on petroleum substitutes from coal. Research was supported, especially on hydrogenation, and the Authority participated in the Joint Australia/Federal Republic of Germany coal-to-oil feasibility study. It also co-ordinated a State Government initiative to involve the private sector in examining the possible establishment of a synthetic fuels industry based on Hunter Valley coal. With a short-fall in world-wide petroleum supply now seen as less likely for some years, the Authority is looking also at ways of working towards the broad objective in the field of coal utilisation on both domestic and export markets. Areas of interest include possibilities for using washery rejects, means of making NSW coal more competitive as an energy source, use of coal-seam gas and new or special technologies for burning coal. The future is expected to see renewed interest in producing petroleum substitutes, and coal - as the State's major energy resource - is seen as a strong contender as a basis for such an industry. Developments in coal-based power generation are also expected to have an impact, with advanced technologies having a possible place here as well as Overseas.

Jan 1, 1987

The Ausmelt Catalytic Waste Converter (CWC) has been developed for use in the treatment of industrial wastes and for the recycling of secondary materials. Ausmelt Technology uses a top submerged lance system within a versatile and efficient slag bath reactor. High temperature pyrometallurgical reactions are carefully controlled within an oxidised molten siliceous slag such that metals can be extracted from waste feedstock for recycling, with non-volatile elements reporting to the slag, usually as oxides. Modification of the slag chemistry results in a final slag product that is stable, vitrified and is able to pass standard leach tests such that it is safe to discard or be used in civil engineering applications. Toxic components in the wastes such as organohalides can be completely destroyed and are prevented from reforming. Waste to energy conversion is practiced by the addition of a heat exchanger/steam generator in the converter offgas system. The Ausmelt CWC has been used for recovering zinc from residues and slags, treating spent potliner (SPL) from the aluminium industry and a wide range of electronic and other potentially valuable waste materials. Methods of monitoring the exhaust gases at different stages in the CWC gas handling system are discussed. The assay of these gases prior to emission is used to assist in the control of the converter chemistry to ensure the complete oxidative breakdown of the feedstock.

Jan 1, 2002

By P D. Williams

The Phoenix mine is one of NewmontÆs open-pit operations located in Nevada. Mining started in 2005, with the mine producing gold, copper and silver. The mine life is about 20 years. The gold grade estimation uses the Newmont in-house indicator kriging approach to handle the high variability in drill hole composite grades and support mining selectivity. Each block contains up to 200 subblocks with different gold grades. A flotation mill is designed to process oxide and sulfide ores, recovering gold, copper, and silver. An additional copper leach process is currently under study to process low gold and high copper oxide material with low copper recovery in the mill. The metallurgical recoveries and processing costs are dependent on many variables including rock formation, metallurgical domain, cyanide soluble copper and sulfide contents. This paper describes the Newmont in-house indicator kriging procedures and the revenue based mine planning software system implemented at Phoenix mine to address the complexity resulting from multi-process, multi-metal and indicator kriging model.

Jan 1, 2007

By Poplawski R. F

A 32-channel PSS seismic monitoring system was commissioned at Mt Charlotte mine in 1994, and at the time it was the first such system in Australian mines. The system continuously observes the occurrence of seismic events and locates them accurately in space and time. Mt Charlotte has a history of seismicity, with the largest event in recent years of Richter magnitude 4.3. The decision to 'go seismic' was made despite some uncertainty regarding its potential usefulness. However after the first year of operation, benefits have been realised in terms of less production downtime, improved mine safety and mine planning, and better understanding of the nature of Mt Charlotte seismicity. The seismic network has performed well, recording 550 events in its first year of operation to a location accuracy averaging ¦ 12 metres. System reliability is excellent, with very little downtime, and acceptable operation and maintenance times and costs. Observations show major distinct changes in the rate of mining induced seismicity over time periods of weeks and months. Events have tended to cluster in specific mine areas and on particular faults and structures. Case examples of pillar preconditioning, breakout around an orepass, and a major stope rockburst, illustrate the role of seismic data and the benefits it brings to safety, productivity and planning.

Jan 1, 1995

The heavy media cyclones at Argyle Diamonds are subjected to extremely abrasive service conditions and have been the subject of a development program from the time the first ore was treated in the AKl processing plant. In the past ten years the cyclones have been re-engineered from a standard DSM design, in which some components would only last four days, to the current Argyle design in which the minimum component life is 175 days. Development has focused upon the elimination of turbulence in the cyclone and combating unavoidable abrasion through the use of appropriate wear materials.

Jan 1, 1996

By A Purton, C Taylor, E Conroy

The spatial modelling of geometallurgical domains is an important step in the characterisation of an ore deposit allowing for the quantification of various rock types, their differing rock properties and the overall value of a project. The traditional approach to modelling such features is through the use of deterministic models, where a single estimate of the extents and structure of the ore deposit is mapped out by geologists based on available data and their interpretation of the geological processes. Any uncertainty in the layout of different domains is not accounted for and heterogeneities of chemical and physical properties of the orebody are likely underestimated. Spatial machine learning techniques can be used to derive geometallurgical categories, or classes, from multiscale, multiresolution and high dimensional measured rock properties. Subsequently, geostatistical simulations of these classes can be applied to obtain multiple equiprobable realisations that define the layout of the geometallurgical classes at unknown locations between boreholes, or domains. In-turn these realisations can be used quantify the uncertainties in the location of boundaries between different domains. The development of a workflow for defining geometallurgical domains and later geostatistically simulating them across the Orebody H; a complex stratabound Bedded Iron Ore deposit located in Western Australia’s Pilbara region is demonstrated. This could be used to identify zones of high uncertainty where collection of additional data might help mitigate or minimise risks and in turn improve forecast production performances.

Mar 22, 2022

By Agrawal R. D, Kapoor M. L

Activity of FeO in the ternary system MgO-FeO-CaO in contact with metallic iron has been measured at 1000 K employing the cell.PtIFe, (Mg, Fe, Ca)OIZr02 - CaOIFe, FeOlPt. Measured data are used to study the phase stability relations in the system MgO-FeO-CaO and an isothermal section at 1000 K through this system is drawn.

Jan 1, 1987

Wetherstones gold deposit is located just east of the township of Lawrence, in the Otago District of the South Island, New Zealand. The paper will describe aspects of the mining and exploration history of the Wetherstones gold field, current knowledge of the geology of the deposit, and speculate on possible outcomes of exploration in the modern era.   As at the famed Gabriels Gully situated nearby, most of the Wetherstones gold is/was contained in, or recycled into modern drainages from, the Blue Spur Conglomerate (æBSCÆ). The BSC is the basal member of a wedge of auriferous non-marine sediments of latest Cretaceous age which are tilted against the Tuapeka Fault Zone, a structure of regional dimensions. In particular mineralisation of elevated grade (which cannot yet be reliably estimated) appears to be concentrated in an elongate basement depression (ægutterÆ) of width around 100 m, variable thickness to a few metres, and axial length in excess of 500 m. The gutter plunges from the base of alluvial mining (where it has been partly exploited by underground methods) to depths of more than 100 m, beyond which it remains open and untested.   The prospects for a revival of mining at Wetherstones depend upon confirmation of what is here inferred to exist, and the discovery of additional gold. The economic prospects of the project however are enhanced by what is known or indicated of the geographic location, and anticipated geologic, mining and metallurgical characteristics of the mineralisation, and consequent anticipated environmental management issues.   The recognition of gold contained in pyrite in the BSC represents an upside to project economics which has never previously been evaluated. The Wetherstones Basin covers more than five square kilometres in areal extent. There is no modern exploration record of the majority of this area, leaving open the prospect of the discovery of additional gutters, and primary mineralisation in the underlying schist.   Australasia Gold Ltd has embarked on a program to reassess the potential resources of the Wetherstones gold mineralisation, and to evaluate the feasibility of mining.

Jan 1, 2004

ecent work on decoppering lead is reviewed; CuS is formed rapidly even from dilute solutions of copper in lead. he mechanism of decoppering is discussed, and an explanation for the retention of metals such as silver in lead is dvanced. As decoppering tin appears to be an analogous process, the Cu-Sn-S system is studied at 300¦C. CuS, hich is not, an equilibrium product, is found in decoppering drosses. In the removal of nickel from lead, Ni3pb2S2 formed; preliminary measurements show the equilibrium nickel content to be greater than that obtained by tirring in sulphur. Decoppering bismuth is thermodynamically favoured, but is complicated by the occurrence of uBiS2. The Cu-Pb-S system is the only one of the four studied where the equilibrium can be calculated simply, as ' resence of ternary sulphide or other phases invalidates calculations based on binary data.

Jan 1, 1970

By G T. Jemwa, F Rousseau, F J. Wolfaardt, J A. M Rademan, P W. Smit

Mining companies are increasingly faced with the challenge of reducing operating costs while maximising throughput and profitability. At the same time, the grade and quality of treated ores are becoming poorer and more variable, resulting in suboptimal process performance.It is now widely accepted that strategies to drive operational goals must revolve around improving plant availability, reliability and process efficiency. In particular, progress in plant automation and control systems has seen a trend towards unified frameworks for control and optimisation of mineral processing plants. These frameworks seek to seamlessly integrate different roles and tasks involved in process operations - IT, automation, plant maintenance and operations. An integrated solution framework for reducing process variability, increasing process efficiencies and maximising plant availability and reliability is discussed within the context of a typical milling circuit. The framework exploits a real-time analysis ægapÆ evident in production operations that prevents timeous identification of equipment and process failures. This is achieved by leveraging predictive analytics for equipment health monitoring, control loop monitoring and advanced regulatory control solutions towards enhanced process performance, improved asset management and regulatory compliance. The framework provides for early and actionable warnings on equipment and process degradation using real-time operational data.Resolving these problems can potentially avoid unplanned downtimes, process instabilities and other operational surprises, thus ensuring optimal plant throughput and optimal process behaviour for improved recoveries. Integrating control systems and plant automation with advanced analytics to analyse and optimise processes enables operations to achieve reductions in the variability of key process parameters. In addition, early detection of equipment malfunction or suboptimal process conditions leads to improved equipment availability and reliability. Ultimately, these operational gains reflect in profitability because of plant throughput and recovery gains. These benefits are demonstrated using data from a South African gold mining operation, where such an integrated asset and process health monitoring framework for process optimisation has been implemented.CITATION:Jemwa, G T, Wolfaardt, F J, Smit, P W, Rademan, J A M and Rousseau, F, 2013. Towards an integrated framework for asset and process health monitoring and optimisation on a milling circuit, in Proceedings World Gold 2013, pp 137-148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

Dynamic hydrothermal modeling is a tool that can aid in studying problems associated with hydrothermal ore deposits and can help increase our understanding of the spatial distribution of ore within hydrothermal systems. Models are constructed by a sequence of steps involving development of a conceptual model, followed by its mathematical description in terms of governing equation with accompanying initial and boundary conditions. This equation is then solved either analytically or numerically. The four model types ò that fully describe a hydrothermal 'system are those for fluid flow, heat and ore solute transport, and deformation. At Renison, models have been used to help understand two major exploration problems. These are the controls on ore localisation in dolomite horizons and feeder faults respectively. The types of models used ò have simulated the distribution of all mineral zones, pyrrhotite, and temperature in the dolomites. This has allowed evaluation of the effects on ore localisation by physical and chemical heterogeneities within the dolomite host rocks, and allowed estimation of potential controls in different physical and chemical environments.

Jan 1, 1987

Both as an energy source and as a raw material, natural gas is playing an increasingly important role as a catalyst for the development, continuation and rebirth of mining projects in Australia. Pipelines are the vital link in making natural gas available to a region and to individual mines. This paper will cover the role of pipelines in supplying mining projects in Australia, the development and status of the Ballera to Mount Isa gas pipeline and the future prospects for gas pipelines in the Carpentaria Mineral Province.

Jan 1, 1998

By P Hayes, B Zhao

A range of materials are treated in zinc fuming processes to recover metal values and produce benign slag waste products. The selection of the optimum process conditions in these various technologies can be greatly assisted by the use of a chemical thermodynamic model of the system. In this paper the effects of slag chemistry on the liquidus temperatures, subliquidus phase equilibria and thermodynamic properties are described by a FACT model of the ZnO-PbO-FeO-Fe2O3-CaO-SiO2 system. In addition new experimental data on the effect of Al2O3 on the liquidus are presented. The implications of these findings for plant practice are discussed.

Jan 1, 2000