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pNumerical modelling has been used to examine the relationship between the results of two commonly used methods of assessing the propensity of coal to spontaneous combustion, the R70 and Relative Ignition Temperature tests, and the likely behaviour in situ. The criticality of various parameters has been examined and a method of utilising critical self-heating parameters has been developed. This study shows that on their own, the laboratory test results do not provide a reliable guide to in situ behaviour but can be used in combination to considerably increase the ability to predict spontaneous combustion behaviour./p

Jan 1, 2005

By Lacy JC

Human habitation of the Pacific Rim began when mankind began migrations out of its place of origin in the Rift Valley of Central Africa c. 4million years ago. This migration was erratic and largely controlled by advances and retreat of the various Ice Ages which, while limiting advances in areas of intense cold, at the same time aided migration thro-ugh the creation of land bridges as ocean levels declined during periods of glacial advance (Fig.l).Mankind began its trek to the Pacific from Africa across India then north into southern China and south into Indonesia (Fig.2). In part, these migrations stimulated early technological develop-ments to fulfill needs and adapt to environmental conditions; thus, these nomads developed stone and bone tools, animal skin clothing and the use of caves and other simple shelters. The earliest evid-ence of mankind's use of fire can be found at Zhou-koudaian near Beijing, c.400,000 BP.From China, the completion of the Pacific Rim's population can be attributed to the last Ice Age that dropped the ocean level by more than 300 feet and created land bridges about 40,000 BP allowing migration across the Bering Strait into Alaska and to Australia from Indonesia. The American migration reached Mexico about 30,000 BP, and by 6000 BP the occupancy of the Pacific Rim was complete when the first human settlers reached the southern tip of Chile.

Jan 1, 1990

By W A. Take, M McKellar, A Walsh, S McDougall, S G. Evans

Recent tailings dam failures have heightened public awareness of the hazard posed by storage facilities for mining waste, illustrating the need for a more critical examination of tailings dam breach mechanisms and the potential mobility of liquefied tailings. Knowledge from tailings dam breach studies will help improve safety and risk management through more accurate inundation maps, dam consequence classifications and emergency preparedness plans. Tailings dams differ from conventional water retaining dams, although dam breach relationships used in practice rely heavily on relationships derived for breach processes from the latter. Physical modelling offers a controlled environment to advance the understanding of tailings dam breach processes, thereby allowing for modelling of simple geometry and boundary conditions to test hypotheses. The performed experiments investigate prototypical tailings dam configurations and material behaviour, with the objective of validating numerical models that will enable practitioners to better assess and mitigate tailings flows resulting from tailings dam failures. Research conducted in the Queen’s University Landslide Flume at the Coastal Engineering Laboratory has investigated the breaching of 1 m high dams with tailings geometry by overtopping initiated by a v-notch incised in the dam crest. This paper presents the initial results of the next stage of this research comparing the outflow hydrograph following loss of containment caused by shear failure to overtopping initiated by notch flow. The two dam experiments presented are constructed with similar dam and reservoir geometries allowing for a direct comparison of the effect on the outflow hydrograph of each failure event. Preliminary outcomes suggest that although both dam failure events are triggered from separate mechanisms their geometries allow for similar values of Q_peak to be reached. Future work is currently planned to expand the shear test series to explore the influence of failure mechanism on the outflow hydrograph.

Jul 1, 2021

By D Cai, E Baafi

Various enabling technologies and systems have recently been introduced in the mining industry. Such systems include miner-bolters with concurrent cutting and bolting, employment of two shuttle cars, adoption of self drilling bolts and utilisation of continuous haulage or monorail systems. The paper discusses how Flexsim discrete event simulation models were used to assess how these proposed mining systems can best be used to achieve and sustain high roadway development rates of 10 m per operating hour for 20 h/day.

Sep 26, 2011

Authorisation No.66 (to Prospect) was allocated to R.W. Miller & Co. Pty. Ltd. on 1st November, 1976. Exploration has brought coal reserves to measured status in the Jerry's Plains sub-group which are about 550m. thick. The immediately lower Vane Sub-group, about 200m. thick, includes about 20 seams. The total measured and indicated reserves of the two sub-groups based on the criteria adopted by the company amount to 1362 million tonnes in situ. This very large resource is subject to very many mining constraints both physical and economic which limit the saleable reserves under present conditions to about 120 million tonnes. The results of the calculation of reserves after exploration is complete in a deep multiple seam situation is dependent upon the criteria used to include or exclude seams in the reserves. These criteria are state- ments of the miner's expectations of the market, mining and coal preparation technology, local and national politics and the law as it may be applied in the future.

Jan 1, 1979

The earliest caveman, very much a minority group, in the face of great adversity and person- al peril, had to take his livelihood by stealth or force of arms - aided by some degree of reas- on and ingenuity. He was pretty much a law unto himself. As time went on, his type became more numerous; and, after bumping heads with the- tough bloke who lived in the cave across the valley, he decided that perhaps he ought to try to get along with him. Perhaps he could trade some over-ripe emu meat for that `roo skin that he had tried to take. Then too, next time he wants a woman, he had better use a lighter club and just stun her a little - that last one was pretty badly bashed. Perhaps he should keep her around the cave and train her to keep the fire going, gather some roots, and skin the game. Those joeys of hers are kind of cute too. Of course they eat, and it would necessitate bringing in more food. So man gained increasing responsib- ilities to his family and neighbours. He domesticated animals, learned that he could cultivate certain plants that were palat- able and would supplement the meat diet, and found that he could modify earth materials to make tools - he became a grazier, a farmer, a miner and a manufacturer. He ceased to be nom- adic and community life came into being. This complicated life and made more rules essential.

Jan 1, 1974

This is a welcome opportunity to exchange ideas about educating for a profession in mining and metallurgy, and I shall use it to highlight the ways in which educators, the industry, and the profession can help one another make that educa- tion better. This is home ground for me in more ways than one. As the executive head of a uni- versity perhaps I may speak as an educator; and there is still, I hope, enough of the metallurgist in me to allow me to speak of what we metal- lurgists and mining engineers can do to help the educators. Another interest should be declared, too. Among the educating agencies I shall focus on universities; among universities I shall further focus on my own, the University of New South Wales. I know it best; and, more to the point, we are one of the minority that offer a full profes- sional training in mining and metallurgy. Further, we are as a university very much concerned- more than most-with specifically professional education, and especially with education in the professions based on science and technology. Mining and metallurgy have of course played a central role, from earliest times onwards, in the history and development of science and tech- nology. In that role they have been both pro- ducers and consumers of new knowledge. Indeed the whole new attitude to knowledge that began to spread in 16th and 17th century Europe owed a great deal to the interests and traditions of the miner and the metallurgist. The first modern text- book of mining and metallurgy, George Agricola's De Re Metallica, is very much more than a spec- ialist handbook; it is a major landmark in intel- lectual and cultural history.

Jan 1, 1978

The word "optimization", refers to the search of an economic optimum, or, more precisely, to the choice of technical parameters which will define the more profitable mining project, knowing the values of the economic parameters. In fact, there is no direct way to perform this optimization, because the extremely large number of technical factors involved, from the type of working and its selectivity to the characteristics of the mill and its flexibility, makes it impossible to make a comprehensive survey of all possible projects. Beside, it would be meaningless to engage in such a task as the deposits themselves are not really known, but only estimated, with sometimes a high level of imprecision. Not to mention the numerical instability which would affect such a computation! In addition, the "best" project is not necessarily the one which strictly maximizes a given profit formula. There also exist human factors which have to be complied with, when choosing the cutoff grades for instance. Finally, there are other non-numerical factors which interfere with the choice between several projects: the shape of the bottom of a pit of the layout of the access road for instance.

Jan 1, 1986

By E Villaescusa

This paper describes a methodology for the design of mine pillars at the McArthur River Mine. The pillar strength is calculated using a method that accounts for confinement, pillar geometry and intact rock properties. The average pillar stress was calculated using in situ measurements of vertical stresses at shallow depth and the tributary area method in conjunction with numerical modelling. Observations of pillar behaviour indicate that an existing pillar stability graph may be slightly conservative and further adjustments for the local rockmass conditions are needed. The results to-date indicate that all mine pillars are stable for a range of mining geometries at McArthur River Mine.

Jan 1, 1998

By Lightfoot BW, Foo KA, Conochie DS

Aberfoyle Limited operated a matte fuming pilot plant, incorporating a SIROSMELT furnace in 1980/81. This plant was a significant advance in both smelting and tin extraction technology. Important design, construction and commissioning aspects are discussed and some of the key points to emerge from this phase of the work are reviewed.

Jan 1, 1984

By A Karrech, A Hasan

This paper presents the numerical simulation of mine backfilling in underground stopes using three-dimensional discrete element modelling (DEM). The simulation predicts the forces exerted at the stope base and barricade with respect to time under free drained conditions. The results of the numerical simulation are validated using basic analytical solutions and advanced experimental tests involving a geotechnical centrifuge system. Overall, a good agreement between the present numerical simulations and the existing experimental and analytical results was found. The present model suggests that DEM is a promising computational tool to predict barricade pressure in underground mine stopes.CITATION:Hasan, A and Karrech, A, 2014. Simulating mine backfill in a fully drained condition using discrete element modelling, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 117–124 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

The paper describes the progress made in the last decade with the introduction of comprehensive monitoring of the mine atmosphere into U.K. collieries. Brief descriptions are given of the various portable and fixed point instruments which have been developed for this purpose and the methods available for transmission of information to the surface are also discussed. The paper also outlines some of the research work being carried out both in the laboratory and underground on the development of alternative methods of fire detection. Some of the results from this work are illustrated and discussed.

Jan 1, 1981

By Terry G. A B

Before detailed design of Museum Station could commence, a number of factors had to be considered to determine its exact location within the city street pattern, the depth and the dimensions of the underground station. To arrive at a sound con- clusion regarding location, the relationship of the station to probable future city development had also to be considered.

Jan 1, 1981

For many years the mining industry at Broken Hill, New South Wales, Australia, was carried on with just sufficient attention to underground ventilation and hygiene conditions as to keep pace with necessity. However, the campaign against industrial diseases in other mining centres (notably South Africa) some years ago, brought the subject more prominently before local mining engineers.Throughout a period of several years, gradual improvement has been effected, and at the present time industrial hygiene is considered an essential part of the production operations of the various companies.In June, 1918, a move was first made by the Board of Trade advising an inquiry respecting the health of employees engaged in the metalliferous mining industry in the State of New South Wales. At the end of that year, a recommendation was made to the State Government by the Board of Trade that a Techni.cal Commission of Inquiry be appointed to examine and report upon the dust conditions of the metalliferous mines at Broken Hill. Following this a second report presented in 1919 made specific recommendations in respect to the scope of such a Commission. A Technical Commission of Inquiry was accordingly appointed and arrived in Broken Hill to inquire into the prevalence of miner's phthisis and pneumonoconiosis in the mines. Early in March, 1920, the examination of all mine employees commenced, and the work was completed in June, 1920. The full report of the activities of the Commission and the conclusions arrived at was officially published at a later date. Based on the recommendations...

Jan 1, 1940

By Smith KS

Mineral-deposit geology, geochemical processes, and biogeochemical processes are fundamental controls on the environmental conditions that exist naturally in mineralized areas prior to mining, and that result from mining and mineral processing. Input from economic geologists and geochemists is therefore crucial to effectively predict, assess, mitigate, and remediate the environmental effects of mineral-resource development. Recent open pit gold mining at Summitville, Colorado, has received intense public scrutiny for a variety of environmental problems, most important of which has been extreme acid drainage. Now a Superfund environmental cleanup site, Summitville exemplifies how economic geology and geochemistry principles (1) could have been better utilized to first predict and minimize the environmental problems, and (2) can now be used to optimize the environmental cleanup.

Jan 1, 1995

By Filmer AO

In contrast to the '50s and '60s, the period of the '80s and '90s seems likely to have low growth in demand but much greater levels of technological change. In such a climate there will be pressure on costs, productivity will continue to rise and competitiveness will be closely associated with maintenance of the most effective technology. The penalties for inappropriate investments, whether short sighted or mistakenly based on a particular view of the future, will be greatly enhanced. Accordingly, there will be a need for significantly improved anticipation of technical change and thus for better planning. Study of the funding and direction of the world's R&D effort can provide a useful input to the planning processes within industries and individual firms. Such a study also suggests some insights into the characteristics of those countries which have achieved substantial growth and high standards of living over the past two decades. These characteristics may offer significant reminders for our own development. The particular implications for the Australian minerals industry include the need for direction that is sensitive to changing market requirements and customer practice. This is not simply "more of the same." In particular it appears essential for both basic and applied R&D to provide a sound basis for the purchase and ongoing development of the new technology required to achieve international Competitiveness.

Jan 1, 1986

By Thompson IR

This paper describes a Client Consultant Relationship and shows how an engineering team created an environ- ment which fosters the development of good, economical and sometimes unique solutions. A major factor in establish- ing this environment was the Client's instruction to the Consultant to "propose solutions which, in the Consultant's considered opinion, best satisfy the needs of the project - not necessarily solutions which reproduce methods adopted elsewhere in the past." The Consultant's experience in other projects and disciplines outside mining has contributed by providing a cross- fertilisation of ideas. The team approach also allows the Client's expertise to be applied positively throughout the design process. These factors and the Client's foresight in providing adequate time for planning, allow the Client-Consultant Team to apply sound fundamental engineering in developing effective solutions.

Jan 1, 1975

By A Flatten, F Reusch

Recent advances in the disciplines involved in simulating large mining operations provide increasingly precise and accurate methods for the study of cave mechanics; however, in large regional-scale models, hydrological aspects are often neglected or studied independently from the mechanical problem. There exists a great demand for a unified approach to study and simulate both the mechanical and hydrological phenomena that allows for a more detailed understanding of the effects of groundwater flow, dewatering and the impact on block cave mining operations.This paper presents a numerical framework that combines three-dimensional regional-scale hydrological simulation techniques for groundwater flow, together with non-linear continuum–discontinuum rock mechanics models, provides such a unified modelling approach. The underlying simulation technique is based on a coupled parallel solution formulation adopting single-phase fluid flow formulations into a discontinuous, strain softening and dilatant finite element model. This approach is adopted for the presented case study of a realistic block caving example in a simplified unidirectional coupling formulation, to investigate the effects of the mechanical analysis on the hydrological response. Here, particular emphasis is on the non-linear coupling of the deformable and strain-softening solid skeleton and fluid phase; eg the change of hydraulic properties with evolution of damage in the rock mass and large-to-intermediate scale structures due to ongoing caving operations. The importance of discontinuum structures is discussed, as mining-induced fault reactivation significantly influences the hydrological response.CITATION:Flatten, A, Reusch, F and Beck, D, 2016. The application of hydromechanical mine-scale modelling for large block caving operations, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 341–348 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By T Martin, M Martin

Mining of sulfide-based ore deposits typically creates a potential for release sulfate and acid to groundwater, and many operating mines are thus predicted to require long-term post-closure treatment of groundwater. Toward the goal of selecting an optimal treatment, this paper compares costs of four demonstrated technologies for long-term treatment of sulfate-contaminated groundwater: in situ biological reduction (ISR), in situ permeable reactive barrier (PRB) composed of compost and zero-valent iron (ZVI), and two ex situ æpump-and-treatÆ technologies ù ex situ biological reduction, and ex situ nanofiltration with lime precipitation. Costs for each technology are estimated for treatment of a model aquifer system containing sulfate-contaminated groundwater, with the goal of treating 1 m3/min of groundwater from 1500 mg/L sulfate to a target level of 500 mg/L. (Metal removal is typically achieved by these technologies, and thus excluded from this analysis.) Costs are estimated for each technology as a function of treatment duration (ten to 60 years) and, for PRB and ISR, required replacement frequency (ten to 60 years). Estimated costs include capital and operation and maintenance, using a seven per cent net discount rate. Results indicate that ex situ technologies (biological reduction and nanofiltration with lime precipitation) are the most expensive. In situ technologies may be much less expensive, with PRBs having by far the lowest potential cost, followed by ISR as the next least expensive. However, actual costs for the in situ technologies are very sensitive to poorly constrained parameters, particularly the ZVI content of the PRB, and the effective life of PRB and ISR systems. This large cost uncertainty supports delaying remedial actions where viable, and suggests that feasibility analyses are generally warranted for specific applications to focus on these sources of uncertainty.

Jan 1, 2003

The Green Parrot and Reward stratabound silver-lead (copper-zinc) deposits are located in the eastern part of the Arunta Block. At Green Parrot, mineralisation is contained within a north-south striking lode horizon comprised of elongate lenses of massive garnet or calcsilicate-carbonate "lode rocks" with intercalated sericite-biotite schist and laminated biotite-feldspar schist. The "lode rocks" are increasingly calcareous to the west. The mineralisation is broadly zoned with an increase in lead content and decreases in copper and silver contents from east to west. The principal sulphide minerals are galena, sphalerite and bornite. The Reward deposit lies adjacent to a lens of massive garnet "lode rock" which is contained within garnetiferous sericite-quartz schist. Primary mineralisation consists of galena, chalcopyrite, sphalerite and pyrite. Both deposits are associated with a substantial thickening of the lode horizon which is narrow and discontinuous along strike from the Green Parrot and Reward deposits.

Jan 1, 1984