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By A Prill

Safety First and zero accidents are the targets most mines in Australia are aiming for, but manual processes and procedures limit the capabilities and response time in emergency situations. Even with a high safety focus, accidents and incidents still happen, too often with tragic outcomes. Dangerous areas, narrow roads and winding curves are all daily obstacles that threaten workforce safety. Every unforeseen event, such as traffic collisions and other accidents, puts lives in danger and weakens production. Safety must be guaranteed.

May 5, 2022

By F

Ore reserve estimation has been described as the most individualistic, the most prickly and even the most controversial of all the technical aspects of the mining profession. This symposium is a great opportunity to look at the present state of the art and full marks must go to the Sydney Branch for organi- sing it at this time. The first essential of good ore esti- mation is probably an awareness of the uncertainties involved, and the possible impli- cations of these uncertainties.

Jan 1, 1979

The BHP Steel Group embarked on a Total Quality Control (TQC) programme in 1984 in response to enquiries from a major customer regarding procedures for quality in materials supply.The TQC initiative has been adopted by all seven Divisions of the Steel Group and covers a broad and comprehensive range of management and workforce improvement initiatives.The development of the TQC initiative in the Collieries Division of BHP Steel over the past eighteen months has resulted in important experiences and leanings.

Jan 1, 1991

By Lynch AJ

Comminution within rod mills has been investigated by izse of a matrix analysis of breakage processes. A para,~ meter, the number of breakage stages, has been introduced and cornfninut-ion within all rod mills has been expressed in terms of the¦1-number of breakage stages- and a function which des--cribes' the feed rate, mill diameter and mill speed.'The effect of variation in feed rate, feed sizing analysis and mill speed on the number of breakage stages-is-,-discussed.

Jan 1, 1963

Orebodies in the Mt. Charlotte - Hannans North Area N. & B. of the town of Kalgoorlie provide a marked'dontrast to the pyrite - telluride lodes of the Golden Mile, although both groups of orebodies appear to be fundamentally related. These highly siliceous telluride free orebodies N. of the Golden Mile are closely related to strong oblique faulting. The Golden Mile. lodes, while possessing an apparent over-all relationship to the oblique faults also have a close relationship to E.-dipping strike faults.

Jan 1, 1964

There is considerable variability in the level of detail incorporated in prefeasibility studies relating to mining developments. Hence, when undertaking a review or audit, it is critical to attempt to ascertain at an early juncture precisely who has compiled the various facets of the study, for what purpose it was intended and the terms of reference given to the authors. Likewise, when commissioned to undertake an audit it is preferable to have proper terms of reference and to be aware of the purpose to which the audit will be put.These factors will influence the degree of detail an auditor would expect to find in the study and consequently, the degree of effort/time required for the audit process. In most instances audits do not imply recalculation of the entire study or modifying it in anyway, but involve an overall assessment of the methodology used, combined with spot checking of detail. One of the most difficult aspects is to determine a realistic order of accuracy for the overall study when the accuracy of the individual components may differ markedly.

Jan 1, 1990

By H Holmstr÷m, A Widerlund, M Lindvall

At the Kristineberg mine in northern Sweden sulfide-rich, poorly buffered tailings have been deposited in five impoundments located along a valley. The tailings area has been remediated by applying a combination of till cover and flooding. A new method that has been applied to parts of the tailings area is to raise the groundwater table to saturate the tailings. By increasing pH by liming, thereby reducing metal mobility, a water-covered downstream impoundment is functioning as a trap for metals released from the till-covered impoundments upstream. In this paper the efficiency of the system approach used at Kristineberg is evaluated. Progressive changes of water quality from groundwater in the upstream till-covered impoundments via surface streams within the pond system to the water in the flooded downstream pond and its outlet are described. The results show that the system approach used in the design of the remediation programme of the tailings works as planned. The sulfide oxidation rate has decreased in the till-covered impoundments, and, as predicted, there is an out-flush of old weathering products which will continue for at least five years before equilibrium is reached. The groundwater in the till-covered impoundments has high concentrations of Fe, S, Mg and Zn, but the concentrations of metals such as Cu, Cd and Pb are much lower than before the till cover was applied. The limed pond is an efficient metal trap, with concentrations as high as 2.76 per cent Zn and 0.28 per cent Cu in the calcite-gypsum sludge developed on the tailings. The outlet from the flooded pond, and thus from the whole mining area, releases small amounts of metals to the recipient in comparison to the amounts that are in movement within the mining area. During the period May to November, 13 kg dissolved Zn and 111 kg particulate Zn was released to the recipient, whereas a total of 27 000 kg was transported by surface water within the impoundment system during the same period. The results from Kristineberg show that when planning remediation of complex mining areas, it is useful to adopt a system approach in which different methods are used on different parts of the area along the flow path of the drainage water, whereas flooding of the downstream pond is the key to the performance of the entire system.

Jan 1, 2003

By I Brunton

Blast fragmentation can have a significant impact on the profitability of a mine. An optimum run of mine (ROM) size distribution is required to maximise the performance of downstream processes. If this fragmentation size distribution can be modelled and controlled, the operation will have made a significant advancement towards improving its performance. Blast fragmentation modelling is an important step in Mine to MillTM optimisation. It allows the estimation of blast fragmentation distributions for a number of different rock mass, blast geometry, and explosive parameters. These distributions can then be modelled in downstream mining and milling processes to determine the optimum blast design. When a blast hole is detonated rock breakage occurs in two different stress regions û compressive and tensile. In the first region, compressive stress waves form a æcrushed zoneÆ directly adjacent to the blast hole. The second region, termed the æcracked zoneÆ, occurs outside the crush one. The widely used Kuz-Ram model does not recognise these two blast regions. In the Kuz-Ram model the mean fragment size from the blast is approximated and is then used to estimate the remaining size distribution. Experience has shown that this model predicts the coarse end reasonably accurately, but it can significantly underestimate the amount of fines generated. As part of the Australian Mineral Industries Research Association (AMIRA) P483A Mine to MillTM project, the Two-Component Model (TCM) and Crush Zone Model (CZM), developed by the Julius Kruttschnitt Mineral Research Centre (JKMRC), were compared and evaluated to measured ROM fragmentation distributions. An important criteria for this comparison was the variation of model results from measured ROM in the fine to intermediate section (1 mm to 100 mm) of the fragmentation curve. This region of the distribution is important for Mine to MillTM optimisation. The comparison of modelled and Split ROM fragmentation distributions has been conducted in harder ores (UCS greater than 80 MPa). Further work involves modelling softer ores. The comparisons will be continued with future site surveys to increase confidence in the comparison of the CZM and TCM to Split results. Stochastic fragmentation modelling will then be conducted to take into account variation of input parameters. A window of possible fragmentation distributions can be compared to those obtained by Split. Following this work, an improved fragmentation model will be developed in response to these findings.

Jan 1, 2001

By K S. Smith, B P. Jackson, P J. Lamothe

The upper Arkansas River south of Leadville, Colorado, USA, contains deposits of fluvial tailings from historical mining operations in the Leadville area. These deposits are possible non-point sources of acid and metal contamination to surface- and ground-water systems. We used stable-metal isotopes to help ascertain metal retention and release mechanisms that influence metal transport from the deposits to shallow ground-water systems. To accomplish this, we excavated an intact core from a small fluvial tailings deposit and performed laboratory column experiments to examine the amount of metals leaching through the core. Deionised water was continuously applied to the top of the core, and effluent was collected from the bottom of the core for a period of about two months. Three saturation conditions were used, including unsaturated, partially saturated, and fully saturated. Reducing conditions developed upon partial and complete saturation of the core. During the unsaturated leaching phase, core effluents were acidic (pH 2.8 - 3.5) and contained elevated metal concentrations. During a portion of the unsaturated leaching phase, stable-metal isotope spikes and conservative tracers were simultaneously applied to the top of the core. The isotopes provide a means to delineate metal behaviour within the core. During the unsaturated leaching phase, the isotope spikes did not exhibit breakthrough with simultaneously added conservative tracers. However, some of the stable-metal isotope spikes did break through when reducing conditions occurred in the core (during the partial- and completesaturation conditions). In this paper, we use Cd as an example of the utility of stable-metal isotopes in geochemical studies. In the case of Cd, after the core was partially saturated, the 111Cd spike was released as evidenced by a change in the Cd isotope ratios in the effluent. This release continued during the fully saturated leaching phase, however, the total Cd concentration did not increase. These results suggest that the 111Cd spike was retained inside the core during the unsaturated leaching phase, and only partially released as reducing conditions developed. Results from this core-leaching experiment indicate there is a large reservoir of water-soluble material within the fluvial tailings deposit, which yields elevated metal concentrations and high acidity, and which may degrade adjacent ground- and surface-water quality. Use of stable metal isotopes in this study facilitated the determination of different metal-retention processes, metal-release processes, and metal sources in the fluvial tailings deposit in response to changing geochemical conditions.

Jan 1, 2003

Batterham and Algie began their paper on: `The role of technology in the minerals industry' (1995) by noting that while: it is often stated that innovation is central to the economic survival of mining and minerals processing in the face of global competition, .. . technology is often far from a core strategy in our industry. This point is correct. Throughout the world, as a broad generalisation, mining companies do not value technology development as a principal means of gaining competitive advantage. It is important to understand why this is the case. Batterham and Algie address this question by making distinctions between innovation, technology and research. They note that while: all successful (mining) companies are good at innovation . . . that innovation can proceed without any research and development and that it is innovation that generates the competitive advantage, not research and development per se. In this paper we accept these arguments. However, our focus is somewhat different. Whereas Batterham and Algie took a mining company's perspective on the technologies of mining and processing, we take a broader view of the opportunities for technology development for company Australia but, in order to focus the argument, we restrict our discussion to the area of mining (rather than processing); we focus particularly on mining systems and mining equipment. We begin by looking at the motivation of companies operating in any industrial sector to invest in research and development. Figure 1 recognises four levels of industrial maturity. For companies in the embryonic and growth stages R&D often is essential to initiating and developing the business. Mining, on the other hand, is a mature industry. In mature industries the conventional roles for R&D are to reduce costs, to extend product differentiation, or to develop new technology with the aim of rejuvenating the business. Next we ask whether these general-industry arguments apply to the mining industry. If they do then the mining industry should value R&D more highly; after all cost reductions and business rejuvenation are goals that are worth achieving. On the other hand if, for whatever reason, these general arguments do not apply to mining then this may lead the mining industry to invest only modestly, or not at all, in R&D. In this event, while this may be a rational decision for the mining industry, it may not be in the best interest of a nation like Australia where revenues from the sale of mineral products represent an important part of the country's economy.

Jan 1, 1997

The kinetics of desorption of nitrogen from molten iron were investigated using the electromagnetic levitation technique. The respective influences of gas flow rate and surface active element (S) were examined. A second order behaviour with respect to the nitrogen concentration in the melt prevailed at all experimental conditions. Sulphur had a marked inhibiting effect on the desorption rate. The experimental results on the rates of nitrogen desorption have been interpreted with the aid of a reaction mechanism consisting of a sequence of elementary steps.

Jan 1, 1991

By Thimons E. D, Derick R. L

In early June, 1986, a fire of unknown origin erupted in one of several main entries of a coal mine located in southwestern Colorado. The fire was aggressively fought with high-expansion foam. As a result of several strategic decisions, the fire appeared to be held in-check. Unfortunately, sufficient quantities of foam were unavailable and as soon as the foam was depleted, control of the fire was lost. To prevent further damage and the possibility of an explosion, all entries to the mine were sealed.

Jan 1, 1988

It should be noted that with the passage of time all aspects of the mineral extraction process are becoming more sophisticated and complex. In order to deal with this, the education system should be geared to this continual technological advance.A new scheme is designed to attract high quality school leaven to take up courses serving the mineral industry. After graduation these students will play an important role in the areas of research and development which is essential for the growth of the Australian mining industry.

Jan 1, 1991

By R H. Boffey

The Osborne copper-gold deposit was discovered in North-West Queensland in 1989. Underground production activities commenced at Osborne deposit in April 1996. This paper will examine technical and operational aspects of the underground mine during its development to a 1.2 Mtpa operation . Technical aspects discussed include geology, mine design and mining methods, equipment fleet selection and capital infrastructure. Operational aspects discussed include the evolution and performance of the integrated work teams that are utilised at Osborne to perform all mining and maintenance activities.

Jan 1, 1998

By R Vleggaar

In addressing a short-term operational need for the relocation of a tailings storage facility reclaim pond, a mine has achieved a host of water management objectives. Through effective planning and adoption of a strategic æwhole of mine lifeÆ approach, the mine has achieved significant environmental, social and economic benefits. A review of all water management aspects across the site identified a host of other interrelated water issues and concerns which, if dealt with individually, would prove too costly for individual operational departments. When considered as a whole, however, the issues became opportunities and provided the stimulus for integration of the site water management system. The development of site water and solute balance models provided the tool by which a number of water management options/strategies could be evaluated. The conceptual design and costing of the proposed water infrastructure further facilitated the evaluation of the multiple benefits to be gained from each option. A business case could then be made to mine management for the preferred option. The recommended water management strategy finally recommended to the mine not only provided a tailings storage facility (TSF) reclaim pond, but also provided for:increased wastewater recovery from the TSF, the capture of all waste rock dump run-off, additional water harvesting from local creeks, increased wastewater reuse, improved environmental water management, infrastructure that could be used by the local community after mine closure, and overall cost savings. This paper illustrates how effective water management planning can provide both short-term economic and environmental benefits, as well as long-term social benefits.

Jan 1, 2006

The author presents various procedures for the choice of dri-ving systems for mining, including the method of indeterminate Lagrange factors and linear programming.The possible application of the points-awarding method is demonstrated.It allows for taking into account both surd and commensurable characteristics of a driving system for mining. Also, the method of economic efficiency factors is outlined.All these methods make possible the best choice of a driving system, from the as-pect of electric energy saving. Two examples are given.

Jan 1, 1985

Comprehensive occupational health and safety legislation in Australia is comparatively recent. It follows the examples set in U.S.A. and U.K. a decade or more ago. In Western Australia the Occupational Health, Safety and Welfare Act was proclaimed in April 1985. It still has a long way to go before it achieves all its objectives. The mining industry has developed a substantial body of health and safety regulations under the Mines Regulation Act. Considerable practical expertise in such matters already exists, much of it developed from hard won experience. As a result it would prefer not to become engulfed in the new legislation. It would prefer to build upon the cooperatively developed policies and workable practices in the field of occupational health and safety with which it is familiar. Associated Minerals Consolidated Ltd. is a leading mineral sands producer in Western Australia and has continuously developed its occupational health and safety policy and practices. Under the banner of "Resource Control", AMC seeks to provide a safe and healthy working environment at all times. This is being achieved through a strategy of a policy, a defined organisational structure and a detailed programme, which together comprise the "Resource Control System". Some of the activities and achievements of AMC in the field of occupational health and safety are compared with the objectives of contemporary legislation, and details of some of the specialised areas of the Resource Control Programme are discussed. The paper will also highlight and discuss impractical areas of potential legislation.

Jan 1, 1986

By Lewis RW, Wilson GI

An ore reserve estimation is only as meaningful as the quality of the data used. All required information needs to be collected in a careful and systematic manner, and be rigorously checked and verified before estimation commences. In addition to geological, assay and location data, a large variety of other information is required for the estimation process. This includes mining, metallurgical and environmental parameters. Though outside their usual area of responsibility, geologists should be involved in the selection and collection of this additional Information.

Jan 1, 1987

I start with some lines from "Pleasures of Hope" by the poet Campbell, published in 1798, which sets the flavour of what I am going to say. They blissful omens bid my spirit see The boundless fields of rapture yet to be; I watch the wheels of Nature's mazy plan, And learn the future by the past of man. I hope to echo the poet's optimistic view of what is yet to come. I am not sure I can find all the omens blissful but we all have some experience of what the wheels of Nature's mazy plan get up to. His advice to learn the future by the past of man seemed sensible to follow, so on the principle that the past of several men would be better than one alone I invited Alan Attwood, Maurice Cahalan, Gavin Moncrieff, Derek Temple, and Peter Wright to help me prepare this address; I am most grateful to them for their contributions. Of the technologies covered in this sequence of keynote addresses, metallurgy is the one which is closest to our consumers. On the age-old principle, which I do not expect to see changed in the 21st Century, that production is about providing the customer with what he wants, when he wants it, where he wants it, and at a price he can afford, I think we should start by trying to see how the market place is likely to develop, and to work back from there to review what technology we need to meet these demands.

Jan 1, 1986

By Diehl GW, Kuntonen J

The Tamrock all-hydraulic rock drilling system 400 has been developed to cover as wide a drilling range as possible, from 35 mm holes in tunnelling, roofbolting and development work to 64mm holes in long hole production drilling. Field experience during the last five years shows that the Tamrock drill covers this range in a way that no other rock drill on the market does and recently the range has been success- fully further expanded to cover bench drilling with 76 mm holes.

Jan 1, 1978