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The paper describes major principals in hydrodynamic test- ing of horizontal and inclined boreholes using flowmetering and pressure build-up techniques while tunnelling and dri- ving permanent workings through water bearing rock and fau- lted zones. A number of case histories is given together with the description of technical means and special equip- ment.

Jan 1, 1988

By Singh RN, Yuejin LI

The problems experienced with longwall mining machinery motivate the development of an expert system for fault diagnosis. The techniques of knowledge representation, database, knowledge base and inference engine guide the selection of the expert systems and languages -"Turbo Prolog"- as exemplified in the case study of hydraulic support. The aim is to hasten future development of a fault diagnosis system and the design of a system to locate and determine the causes of failure of longwall machinery. The system would use its stored case history and other information to make fault diagnoses and suggest appropriate remedies. Consequently down-time would be reduced and production and profitability should increase.

Jan 1, 1991

The geotechnical and environmental aspects of heap leaching are very closely tied during design, operations and closure. Potential environmental impacts from heap leaching are mostly due to land disturbance and water quality issues, including both groundwater and surface water. Water quality issues are mostly related to containment design, which is primarily a function of proper sizing of the facilities and site specific liner design. Geotechnical analyses is the dominant discipline in providing cost efficient, operationally effective and environmentally sound heap leach facility designs. Much has been published on geotechnical aspects of heap leach design, for example Van Zyl, Hutchison and Kiel (1988) and Van Zyl (1987). This paper will emphasize a few specific aspects related to the geotechnical and environmental consideration for heap leach projects. These aspects are: ò site investigation; ò containment design; ò slope stability; ò heap flow dynamics; and ò closure design. Design of a heap leach project must consider not only the operating life but also closure and post-closure considerations. As a matter of standard practice, designing for closure is an extremely important concept. Not only is it important for environmental aspects, but experience also shows that projects designed for closure will be overall more economical for the total life cycle of the project. Closure considerations are also important during project feasibility evaluations to ensure that total life cycle costs are evaluated.

Jan 1, 1994

By J Stiefenhofer

"*This is an abstract only*Construction of geological models for kimberlites has historically largely been based on visual volcanic textures and features, with chemical data only collected on an ad-hoc basis depending on the level of perceived complexity observed in the geological data. The focus of this paper is a high-level view of the impact an initial absence (or lack) of relevant chemical data had on two kimberlite resource models as well as how the magnitude of the problem increased once the resource estimation process commenced (Stiefenhofer, 2013). The impact of ignoring chemical data on a project assessment where micro-diamond estimation techniques are employed, is also discussed. Resource estimates based on micro-diamond data are critically dependent on the use of the correct geological model since stationarity of the size frequency distribution is key to the generation of correct grade estimates. A multilevel approach is advocated where the volcanological/visual model is verified using chemical data and both are in turn verified by the diamond data.CITATION:Stiefenhofer, J, 2013. The use of chemical and metallurgical parameters to enhance the economic value of kimberlite resource models, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013, pp 101-104 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Sep 29, 2013

The accuracy with which block values are known can have a fundamental effect on the success of an operation.From a geostatistical study the variance of the error in extending sample values to block values can be determined and the engineer must ensure that this is sufficiently small by adjusting the size of blocks or moreintensive sampling. A study is given for a deposit showing a high degree of anisotropy and it is shown that the shape of the block is not important in determining the estimates.

Jan 1, 1976

By P D. Erskine, A Hine

The current Queensland Government’s rehabilitation guidelines for post-mining landforms present a hierarchy of preferred outcomes for different areas within the mine site (see Figure 1). Within all areas, restoration of a ‘natural’ ecosystem is clearly prioritised as the preferred end land use, although it is not a mandatory practice. Beyond the official guidelines, there is also an implied preference for renaturalisation echoed in most environmental impact assessments and closure plans (Lamb, Erskine and Fletcher, 2015). In practice, however, ecosystem restoration does not extend to construction of a realistic topographic form, largely rejecting the ‘natural’ aesthetic implied by ecosystem restoration in favour of adopting a functional aesthetic in deference to standard engineering criteria.This presentation argues that the established disconnection between actual and implied landform aesthetics is indicative of a wider problem around end landform planning. It contends that such disconnects are the result of the impact of competing ‘ways of seeing’ (Bradley and Kearney, 2007) the same landscape, and reflect the struggle between, and inclusion of, these differing perspectives within the planning process itself. We propose that recognition of the complexity of landscape perceptions is key to improving post-mining landscape outcomes, and the misalignment between land use values and landscape aesthetics can be addressed by establishing an overarching framework for landscape preferences. As such, we outline the reality of stakeholder landscape preferences, and present a critical response to current planning practices within the life-of-mine (LOM).CITATION:Hine, A and Erskine, P, 2016. Recognising and integrating stakeholder landform expectations into life-of-mine planning, in Proceedings Life-of-Mine 2016 Conference, pp 154–157 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

This paper describes some of the challenges and opportunities of contract mining overseas, based on the experiences of Byrnecut Mining Pty Ltd over recent years. It seeks to highlight the advantages Australian miners have compared to competitors around the world, and the opportunities that arise from that. A number of pitfalls and how to avoid them are also discussed.

Jan 1, 2002

By Riley TW

This paper describes a Process Simulation Package for modelling the steady-state operation of a mineral processing plant. There are two levels of input allowed into the package. The first allows simple manipulation of the process models within a defined modular format which enables a wide range of process systems to be simulated. "The second level of input is via a Command file which allows plant models to be defined and changed without reference to the code or the requirement of any recompiling of the programme sources. The Command file interface was designed for use by metallurgists and assumes a sound knowledge of the system being modelled. As such it is an effective tool for metallurgists rather than a user friendly generalised package for the layman.

Jan 1, 1985

A case is made for broader commercial education of executive and operational managers in Australian mining companies. The competitive advantages and disadvantages of Australian miners are examined. Areas of opportunity are identified which could be exploited by broader applications of proven techniques to commercial management of mining companies.

Jan 1, 1985

The Adavale Basin and Warrabin Trough are remnants of a much more extensive Devonian to Carboniferous depression which evolved through four tectonic stages; an initial period of rifting and three periods of foreland thrusting, which cannibalized much of the earlier depression. The Basin has subsequently been buried by sediments of the Galilee and Eromanga Basins.The Basin was initiated during the Early Devonian when the earlier cratonized Thompson Foldbelt rifted away to form a marginal sea comparable to the South China sea. This crustal extension was probably in a Northeast-Southwest direction. These initial rifts were the site of acid volcanism (Gumbarbo Formation) and later, deltaic and shallow marine facies (Eastwood Beds).

Jan 1, 1990

Crystalline glass defects (usually referred to as stones) come in a wide range of compositions and from a variety of sources. Complete identification requires a determination of the mineral phases present and their textural arrangement. Until the source has been determined, no remedial action can be taken to eliminate the problem.

Jan 1, 1989

The Benambra deposits, which are regarded as volcanogenic in origin, may be subdivided into two major bodies, termed the Wilga and the Currawong deposits; these are further subdivided into smaller, more manageable units, based on composition and structure/spatial distribution.

Jan 1, 1989

The integration of economic, cultural, social and environmental decision-making has increasingly become globally recognised as the only acceptable way of doing business consistent with sustainable development. This concept requires a move to a new economy, where environmental, cultural and social issues are accounted for and integrated in business decisions and practice. There has been much discussion on sustainability and sustainable development, but organisations are still grappling with what this means in reality for their business and how they should respond. The challenge is to take the way we do business to a new paradigm and make solutions relevant to business. This paper will look at some of the strategies and programs being adopted or considered by resource companies as they move towards a more sustainable future. These include defining a sustainability framework for their organisation, developing the business case and planning approach. Also included is a brief overview of some of the new approaches to environmental management, such as reducing materials and energy intensity, minimising or eliminating impacts through better waste and emissions management and process control, taking a whole of life approach to products and conserving resources. The concepts of Product Stewardship, Eco-efficiency and Cleaner Production will all be discussed.

Jan 1, 2002

By J Lim, M Powell, P J. Scales

The current philosophy employed in the design of mineral processing plants effectively involves bolting together segmented unit operations both chosen and optimised from a product-centric perspective. In this context, integration of water saving technologies at an overall plant level becomes difficult and often only local water efficiency improvements are feasible. In general only limited benefit can be obtained from such add-on solutions. It is therefore proposed that to obtain significant savings in water consumption and reductions in the volume of discharged contaminated water in the mining process, the entire process along the mining and mineral processing chain should be addressed This paper explores aspects of the processes that may be modified to provide an integrated and combined step change saving in water consumption. It is also apparent from this study that taking a more holistic view of the process can provide significant benefits in energy savings and total cost of production, providing the potential of a substantial win-win outcome.

Jan 1, 2009

As economic, technological, regulatory and other forces continue to present the global mining industry with new opportunities and challenges, agile mining equipment manufacturers are stepping up their efforts to anticipate and meet the evolving needs of surface and underground mining operations. Operational excellence û the pursuit of efficient, lowest-possible-cost production û is a prime objective for all mines. As mineral commodity markets experience cyclical price highs and lows, mine operators, increasingly, look to their equipment suppliers for equipment and support that can help reduce multiple tangible and intangible operating costs. This paper explores how two mining equipment manufacturers û P&H Mining Equipment, a supplier of surface mining equipment and Joy Mining Machinery, a supplier of machinery for underground mining û are responding to the mining industryÆs aggressive pursuit of obtaining reduced operating cost with innovative products and support programs.

Jan 1, 2000

The basic principles of mineral valuation were recognised and propounded at the beginning of this century and have remained virtually unchanged since then. Valuation is seen as a two part process commencing with a technical examination of the mineral property followed by a manipulation of the results of the technical examination in order to determine the monetary value of the project. A thorough and competent technical examination was seen then and remains now as the essential but not sufficient foundation for reliable valuation. All authors stressed the need to maintain the integrity of the data base and to ensure adequate coverage of all relevant aspects. The monetary valuation process through most of the first half of this century was mainly based on the Hoskold two rate method, derived from the formulae for valuing annuities but modified to provide explicitly for recovery of capital. Though the basic principles of valuation have not changed significantly, the means of implementing the components of the technical examination, the styles of deposits being evaluated and the mechanisms of monetary valuation have changed dramatically. Despite all the technological improvements, however, mineral valuations are still as apt to vary from realised performance as at any time in the past. As well, mineral property valuations are now being extended to cover all assets of potential value, including valuation of exploration tenements with or without identified resources. Valuation of exploration tenements will continue to be one of the most difficult and contentious of valuation tasks.

Jan 1, 1994

Just as Australia is part of the Pacific Rim, so the Pacific Rim should be viewed as part of the whole world. That applies in particular to that scarce commodity û money. There are five main factors of production in any mining development û mineralisation, materials, manpower, management and money. LetÆs focus on the upstream input û mineralisation, and the downstream input û money, especially in the area of communications. Unknown to many, the Competent Person reporting on Mineral Resources and Mineral Reserves has a direct and unavoidable impact on the companyÆs financial statements û the profit and loss account and balance sheet. With respect to reporting of the major asset of most mining companies û the resources/reserves û investors are getting a better deal now than at any time in memory as regards flow and adequacy of information. Australia has been a world leader in this regard. The outlook is for even more informative and useful reporting. The more rigorous reporting requirements for Exploration Results and Mineral Resources/Reserves, which have become a worldwide phenomenon over the last five years, will continue. This will be positive for the mining industry as a whole and for Australia in particular. However competition for the scarce investment dollar will also increase. Put simply, mining has many competitors, unconnected with mining, for the capture of the investment dollar. It behoves all participants to recognise that there are three investment factors which influence strongly the willingness of investors to put money into mining. These are Confidence, Credibility and Consistency. AustraliaÆs investment image stands high in these three respects, but the competition will continue to grow. AustraliaÆs lead must be maintained. However, some investment decisions should not necessarily be based on fundamental, quantifiable facors. Some of these are outlined.

Jan 1, 2004

The gold industry has been revolutionized in the last decade by market forces and technological changes. The latter are discussed in this paper, with particular emphasis on carbon-in-pulp (CIP) and heap leaching. The nature and scope of the process development aspects of a gold project are considered, and factors which determine process decisions are outlined, including the choice of CIP versus carbon-in-leach (CIL), agitated leaching versus heap leaching and treatment of ores containing copper and silver. Likely directions for development of gold processing in general are discussed, and metallurgical process options for treatment of ores of platinum group metals (PGM) are outlined.Metallurgical process development for gold and platinum group metals proceeds through a number of well defined stages, with input from various disciplines and information sources. The orientation phase will include preparation of a general project overview; careful consideration of the issue of sampling and sample preparation; characterisation of the resource in terms of ore types, mineralogy, chemical composition; development of appropriate methodology; and development of an understanding of the potential metallurgical unit operations.The process definition phase will be-'directed to development and definition of a notional process flowsheet, and will include identification and appraisal of process options; development of, notional process flowsheets; testing of flowsheets against ore types; ranking of flowsheets; initial engineering, including preliminary mass balances, equipment selection and plant layout; and broad-brush economic appraisal.

Jan 1, 1986

By M Fisher, P Bradley, D Rogers

New England Antimony Mines has operated the Hillgrove Gold Plant at Hillgrove in New South Wales since 1969, producing stibnite and arsenopyrite products by selective flotation. Gold is present in the ore as fine free gold, gold associated with stibnite and gold associated with arsenopyrite, with some ten to 20 per cent of the gold reporting to the antimony stream and 35 - 50 per cent reporting to the arsenopyrite stream. Opportunity to process the arsenopyrite concentrate for onsite recovery of the gold values to improve upon the ten per cent recovery achieved by conventional cyanidation was recognised and subject to comparison with biological oxidation, roasting, nitric acid oxidation, low temperature oxidation (Activox«) and conventional pressure oxidation. Following further testwork and a feasibility study, a 7500 tonnes per annum concentrate feed pressure oxidation autoclave circuit was constructed at Hillgrove and commissioned in October 1999. The plant has operated at the close to design capacity since commissioning whilst optimising various operational and metallurgical aspects. The last three years has seen the process achieve an overall gold recovery of greater than 90 per cent for oxidised concentrates.

Jan 1, 2002

Titanium dioxide (TiG ) is produced 2 commercially by two methods generally referred to as the "sulfate" route and the "chloride" route. The SCM Corporation, in supplying 15% of the world's demand for TiO 2, uses both of these processes. Of the two processes the sulfate route is generally regarded as the older and more established technology. Worldwide the sulfate route accounts for some 70% of total Ti02 production. However, in the U.S.A. the chloride process accounts for 80% of production. The processes vary in chemistry and raw material requirements. In the "sulfate" process finely ground ilmenite or titanium slag is digested with sulfuric acid to produce a porous "cake" vrnich is extracted with water and recovered liquor. The solution is treated with scrap iron to reduce any ferric ions to the ferrous state which is then crystallised and removed as ferrous sulfate heptahydrate. The liquor is concentrated by evaporation and hydrolysed to form the insoluble hydroxide which is filtered and washed free of impurities. This is converted to the dioxide by calcination at 800 - 1000¦C and milled to break up any aggregates. The "chloride" process uses a higher quality feedstock of natural or synthetic rutile and/or high grade titania slag. The feedstock is mixed with ground high-purity coke and chlorinated at 950¦C in a fluidised bed. The resulting crude titanium tetrachloride is purified by distillation and chemical treatment. The purified titanium tetrachloride is burned with oxygen or oxygen enriched air to give titanium dioxide and chlorine, which is recovered and recycled to chlorination. Titanium dioxide pigment from both processing routes undergoes similar finishing techniques. It is subjected to further stages of wet and dry milling, then coated with layers of inorganic oxides in order to enhance its properties for specialist applications.

Jan 1, 1986