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By J Watson, C Zhang, I Canbulat, C Wei

Coal burst is defined as a dynamic release of energy within the rock or coal mass in underground coalmines that causes violent rock or coal ejection in the vicinity of mine excavations. It poses one of the highest safety and productivity risks in the mining industry as coal bursts have the potential to cause multiple fatalities. As Australian coalmines go deeper, the likelihood of coal burst increases. Thus, it is critical to assess the ground support requirements in coal burst-prone conditions. A previous study conducted by the authors (Wei et al, 2022) reviewed the support capacities of a wide range of ground support elements in laboratory tests. This study aims to examine the role and effects of the ground support elements and systems for Australian underground coalmines to minimise the damage caused by catastrophic dynamic failures (ie coal and rock burst) and enhance the safety of mine workers.

Nov 29, 2022

By Higuchi K, Sekimoto Y

In this report,the results of the large diameter drilling tests in coal seams assisted with water jet are described. The stress relief in coal seams by this new method is as effective as by the conventional method and the penetration speed by this method is 1.5 times as fast as by the other method. 1 Introduction The average mining depth of Japanese coal mines has already attained about 700m from the surface. Almost all coal mines are suffered from occurrence of coal and gas outbursts. To prevent outbursts, some countermeasures are taken generally. In particular, large diameter stress relief borings have been carried out quite often at Akabira coal mine located in the northern part of the Ishikari coal field in Hokkaido,JAPAN. These borings have had successful results but the drilling work of such large diameter

Jan 1, 1987

Mining companies around the world are seeking methods to coordinate operations between the mine and the concentrator to achieve an overall improvement in enterprise performance. In several instances very significant increases in productivity (more than 20 per cent) and profitability (more than $US 10M per annum) have resulted from such efforts. The key to realising these large benefits has for the most part arisen from improved communication between mining operations and plant operations personnel and the judicious use of new tools to evaluate alternatives for improvement and to minimise the risk of implementation. This paper presents a systematic approach to mine-to-mill optimisation . The importance of systemic thinking and systems optimisation methodologies is emphasised. New tools for evaluating operational performance are discussed. Recently reported benefits are summarised. Finally current research is discussed and projections for the future are given.

Jan 1, 2000

By Real F, Carvalho P

During the development of the Neves-Corvo Underground Copper Mine, since 1981, inflow of water has been encountered in the mine workings, which consist of a ramp from surface 5 km long, a shaft 575 m deep and access crosscuts through the massive sulphide orebodies of Neves, Corvo and Graga, which are three of the four known deposits up today. Mine-hydrological studies have established the main characteristics of the hydrological system and its evolution in space and time. In a geological setting of low permeability rocks of Paleozoic age, tectonically affected by thrusts and faults, this has involved consideration of the relation with surface and ground water as a result of mine dewatering processes. The hydrological systems are described and summarized in this paper together with the techniques employed to study their origin and evolution, namely hydrochemistry, thermometry, piezometry and isotopic tracers.

Jan 1, 1988

By D M. Frantois-Bongarton

"A few situations are first reviewed where practical shortcuts lead to acceptable solutions where none seemed to be possible. These include: The solving of many complex sampling optimisation problems with the simple approach of the worst case policy (WCP). A simple approach to single-stage sampling problems will be mentioned at continuation. In the plants, minimising the impact of border effects in incorrect samplers, so that the resulting samples are approximately correct and acceptable in practice because the bias risk attached to them is controlled. Examples are given, as well as practical tools and a general methodology.Finally, some sources of undue conservatism are reviewed with general recommendations aiming at eliminating them.CITATION:Frantois-Bongarton, D M, 2012. Practical considerations and shortcuts in sampling, in Proceedings Sampling 2012, pp 171-174 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 21, 2012

By D M. Frantois-Bongarton

Variograms can be powerful tools for the analysis and control of process streams and their sampling. Their uses and proper utilisation have been described somewhat unclearly to date, and their limitations and precautions of use are too rarely mentioned. The general meaning and properties of the variogram tool and its use in geostatistics are therefore reviewed in details to derive a critical view of its proper use for process control: what to expect from it and what it cannot deliver and which uses are illusory or potentially misleading. A summary of GyÆs seminal work accompanies this essay to put the concepts into historical perspective.CITATION:Frantois-Bongarton, D M, 2012. Review of variogram properties and remarks on its use in process control, in Proceedings Sampling 2012 , pp 175-180 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

This address was delivered at the Annual Conference Presidential Dinner held in Sydney on 11 July 1988.The Australasian Institute of Mining and Metallurgy brings together, voluntarily, people with a professional interest in the disciplines and skills which are employed in the mineral industry, and in relation to that industry.We come together because we have a mutual interest in improving what is done by the mineral industry, in all its aspects. It is this sense of continuing improvement, of doing better, of doing as well as we can, as our knowledge and skills improve, that unites us in creating and fostering a professional association of likeminded people.We know from our professional training and experience that enormous progress has been made, at an ever-increasing rate, in the mineral industry, particularly this century. We know that the mineral industry has played a very major role in providing the means by which so many more people survive to live longer, healthier ,and more interesting lives, than ever before. Indeed, together with the oil and gas industry, which is an integral part of the mineral industry but has achieved its own commercial distinction, it is fair to claim that the mineral industry has played the major role in providing the means for the advancement of the human, quality of life.We do not need to make any great claims on human society in consequence of our statement of these contributions. The facts, for those who are aware of them, speak for themselves. Our more modest interest, as members of our professional association, is to look to the future, while conscious of our heritage as a guide to what more might be done, in that future.We certainly do not claim that this indisputable contribution made to human welfare by the mineral industry gives us some moral position of superiority from which to claim greater support or understanding from the wider community of people.On the other hand we know that as members of the mineral industry we have a responsibility to do what we can to help other people to be aware of, and to understand the significance of, those facts which will only speak for themselves if we take the trouble to make them known. And we have a number of organisations. The Institute itself, The Australian Mining Industry Council, the various State Chambers of Mines, the industrial relations body, The Australian Mines and Metals Association, and others, each of which in its own way endeavours to add strength to the individual efforts which we each should make.We may look at these facts about our mineral industry as simple dry statistics, even with their undoubtedly improving trends, or we can see them, and portray them to others, as expressing something which is much more. We can portray them as expressing the outcomes of our professional determination to strive to do better, whatever it i,s we find ourselves doing in this mineralindustry.We may seek to describe our efforts as being in pursuit of excellence, or by other such high-sounding phrases, but I prefer to describe those efforts as simply our strivings to make everything we do better next time-much as the dedicated golfer tries to do, but with, may I suggest, more evident success achieved in the mineral industry; which is one reason why I don't try to play golf.May I suggest to you that trying to do better, is very simply the true basis of professionalism? We are trained and practised to see the opportunity for improvement-not to be static in a world which we know is changing so rapidly in every aspect around us. We must be dynamic, which means optimistic, about improving the world in which we find ourselves.

Jan 1, 1988

By Lawson F

Arsenic-containing waste was dissolved into molten slags and the leaching behaviour of the quenched arsenic-doped slags (containing up to 2.3 wt per cent arsenic) was ascertained to evaluate the potential of this method as a means for arsenic disposal. The leaching behaviour was evaluated using acetic and sulphuric/nitric acid based solutions.From short-term (18 hour) leach tests, the amounts of arsenic in the leach solutions were found generally to decrease with an increase in the Fe(III)/Fe(total) ratio of the slag or an increase in pH of the leach solution. The amount of arsenic in solution increased with an increase in the slag basicity, the slag arsenic concentration or the surface area of the slag exposed to the leach solution. From longer term leach tests (up to 40 weeks) in the pH range 5 to 8, the arsenic remaining in the leach solution was believed to be controlled by sorption processes. The sorbent was an iron oxide-rich material which had the capacity to lower the arsenic concentration in the leach bottles to well below 1 ppm in some cases. At a leach solution pH over 9, the arsenic concentration in the solution increased with time, although the rate of solubilisation was much slower due to the high pH.Slags have the potential to stabilise arsenic and prevent it entering the environment provided attention is paid to the slag chemical composition and oxygen potential.

Jan 1, 1996

By Komosa T, Muir D. M

Mixtures of ammonia and cyanide at low concentrations leach gold selectively from copper-gold ores. The effects of various reagent compositions on three different ore types containing between 0.3 - 1.5 per cent Cu are reported. It is shown that the results and optimum compositions vary according to the ore, which is attributed in part to the mineralogy and adsorption of solution species on the mineral surfaces. The solution chemistry of the Cu-NH3-CN system indicates that Cu(CN)a - and Cu(CN)3 species are involved in the leaching mechanism. Rotating disc studies on pure gold and copper are reported which show that the Cu(CN)32- species leach gold at about half the rate of CN but leach copper at the same rate. The presence of ammonia retards the leaching rate further. Mixtures of Cu(CN)a3- and NH3 effectively leach gold from Telfer tailing without leaching copper. The role of ammonia appears to be to control the precipitation of copper rather than the kinetics of leaching.

Jan 1, 1991

What is `environmental risk'? There are two possible perspectives: (a) The risk that mining activity will have an impact on the environment. (b) The risk that due to a perceived impact on the environment, the mining activity is at risk due to some legal consequence. This paper is concerned with the second of these perspectives, and particularly with the way in which mining companies can manage that risk. Environmental risk - possible legal consequences The risk is that the mining operation will be disrupted. Disruption may be: (a) Physical. The mining activity can be stopped, altered, or modified, or something additional can be required to be done. (b) Financial. Penalties (up to $1M) on corporations and in some states on both directors and managers. Land may also be included on a contaminated land register (significant impact on asset valuation).

Jan 1, 1994

Visual computing opens the design process to a wider audience and allows rapid communication of mine plans to all stakeholders. The integration of software and hardware technologies that take advantage of a graphical environment will continue to improve both long-term and short-term mine design (Figure 1). A good design must be adaptive to respond to decision changes as the mine develops and more information becomes available. The constraints on mine design predicate careful analysis in order to operate the mine as efficiently and safely as possible.Continuous improvement in mining is assured by developing innovative technologies that target mine survey, drill and blast, modelling, short-term design and pit and stope optimisers. The design life of a mine has to be sufficiently long to ensure the mine is commercially successful, justifying the high start-up capital costs. Being able to execute a plan so that it honours the design realises the rewards of computerised mine planning and the long-term investment in data acquisition.

Sep 26, 2011

This paper is intended to continue the subject in the light of recent work, from where it was left at the conclusion of the discussion on the excellent paper by the late Mr. Noel Haszard. The position then obtaining is briefly summarised below:-The points which received general agreement at that time were:-'(1) That the gold occurs, probably in an elemental form, in a state of very fine division in the pyrite.(2) That the aim in roasting of Kalgoorlie flotation concentrates should be to obtain the maximum porosity possible. The gold tellurides were amenable to treatment with either a' solution of high lime and cyanide strength combined with fine grinding, or bybromocyanidation without re-grinding.(3) That a low roasting temperature is essential during the elimination of the first atom of sulphur, if the final calcine is to give a good extraction by cyanidation.(4) Even with the best temperature conditions of roasting then determined, and after a period of cyanidation of the calcines until no further extraction was obtainable, the lowest calcine residues obtainable were equivalent to approximately 1·8 dwts. per long ton, based on an original concentrate of pure pyrite.There was some division of opinion at the time as to whether the temperature of the later stages of roasting was significant, and also as to the reason why the initial roasting temperatures had so marked an effect.

Jan 1, 1939

Teller Underground Mine was established to extract ore from the Middle Vale Reef located on the eastern flank of Telfer Main Dome.The mine is located below a 150 m deep open pit operation. The ore body is shallow dipping highly structured, and is a main aquifer in quite difficult ground conditions.In respect of these conditions it was determined to access the orebody using an adaptation of coal mining and hard rock mining methods, with support being achieved using a combination of island pillars, rock bolts and timber stalls.The paper will describe these methods in more detail, then discuss the successes and failures of these methods when put into practice. As well, it will detail several factors whose influences were found to be greater than previously expected and stress the importance of good geotechnical advice.

Jan 1, 1993

By Winter W, Steele DA, Trudu AG, Gray CM

The Luzon arc extends for about 900 km from Taiwan to the island of Mindoro (central Philippines); in this area late Tertiary to Recent volcanism is considered to be the result of eastward subduction along the Manila Trench. The arc is composed of five segments, all of which have individual characteristics with respect to tectonic setting and magma chemistry (Defant et al., 1989). From the north to the south these are (Fig. 1): (1) the eastern Coast Ranges of Taiwan and the islands Lan-Hsu and Lu-Tao (Taiwan Segment), (2) the islands off the north coast of Luzon (Babuyan Segment), (3) the Northern Luzon Segment, (4) the Bataan Segment, and (5) the Mindoro Segment. Defant et al. (1988) suggest that the Bataan and Mindoro segments of the arc, both of which are characterized by different isotopic compositions and levels of large ion lithophile element (LILE) enrichment in the lavas, are separated by a 'pull-apart' zone, the Macolod Corridor.We are currently studying the mineralogy and petrochemistry of Late-Miocene to Pliocene volcanism in the Northern Luzon Segment (NLS), which comprises the geographic area of the Cordillera Central. This area has so far received limited attention, inspite of its wealth of porphyry copper, skarn and epithermal gold deposits. In this contribution we report the first results of our study of igneous rocks from the Mankayan Mineral District (MMD) which is located in the centre of the arc segment under consideration.

Jan 1, 1990

By Caivin JS, Freeman CJ

The Fairbanks Mining District in central Alaska was discovered in 1902 and since then approximately 7.5 million troy oz of placer gold, 250,000 troy oz of lode gold, and several thousand short tons of antimony and tungsten hap been produced from an area of about 1000 km . Historic lode production was from high grade gold-quartz veins that averaged 1.3 OPT free milling gold. Five main types of mineral deposits' are recognized in the district. I. Conformable, stratabound volcanogenic zinc, antimony, lead, and copper sulfides in places containing gold, silver and tungsten in bimodal metavoleanics (Cleary Sequence). II. Complex precious metal-bearing lead sulfosalt-quartz veins in Cretaceous granitic intrusives. III. Tungsten skarns adjacent to granitic intrusives. IV. Gold-bearing polymetallic sulfide-quartz veins crosscutting metavolcanics and metasedimentary units of the Cleary Sequence. V. Antimony-bearing gash veins along axial plane shears in various lithologies of the Cleary Sequence. Type I and Type IV mineral occurrences are currently being evaluated as low. grade bulk tonnage (target model 16-20 'million tons of 0.05 to 0.15 OPT)'and high grade moderate tonnage (target model 0.5 to 2.5 million tons of 0.5 OPT) gold deposits. The host rocks for Type I mineralization occur over a 30 km strike length and are at least 300 meters thick. Stratigraphic, structural, fluid inclusion, and isotopic data suggest that the Type IV mineralization is related to remobilization of Type I

Jan 1, 1987

By A B. Christie, R Barker

Recent studies carried out to support the development of a strategy for the New Zealand mineral industry by the NZ Minerals Industry Association have included investigations of mineral potential, and the development of scenarios for realising this countryÆs mineral potential by 2010. New economic research is applying a general equilibrium model to quantify the opportunity cost of this potential. The model analyses separately four categories of land (private land and three categories of Crown land) and identifies four distinct mineral classes û precious metals, industrial minerals, coal and aggregate. It investigates the economic effect of the increased availability of mineral resources on the mining industry itself, on other industry sectors and on the NZ economy generally, including its impact on unemployment, GDP and household welfare.The analyses suggest that increases in the level of GDP of between 1.9 per cent and 3.4 per cent may be obtained by utilising New ZealandÆs mineral wealth to varying degrees. The mineral industry sectors are significant beneficiaries under all scenarios; mineral output increases by between two and five times its current level. However, the flow-on effects to the rest of the economy, and to households, are also significant. The analyses show that household income, adjusted for changes in consumer prices, can be expected to increase by between 1.6 per cent and 2.7 per cent. This results largely from increased employment.

Jan 1, 2002

The equipment and general smelter layout for the Mount Isa Copper Smelter were designed by engineers associated with the American Smelting and Refining Company and by Mount Isa staff engineers. The final notice of site was dictated by the need for 'building the smelter near the existing Mount Isa power house to enable full use to be made of the steam from the waste heat boilers. Although much excavation work was necessary before concrete foundations could be poured, the location lends itself to further expansion should it become necessary. The plant is designed and constructed to involve straight line smelting operations which include the following major steps in the overall scheme.1. Charge make-up.2. Roasthig.3. Reverberatory smelting.4. Converting.5. Refining.6. Casting.CHARGE MAKE-UPA system of proportioning bins is provided for preparing the feed mixture for the roasters, Sulphide concentrate containing 24% copper wiil be delivered by belt conveyor from the filter plant to the smelter storage patio. This is a large roofed concrete floor that provides a maximum storage capacity of 8,000 tons of concentrate. Eight proportioning bins located below but adjacent to the south end of the patio will be used for actual charge make-up from which concentrate, ore and flux will be proportioned to the feed belt and conveyed to the roaster feed hoppers. Four of the proportioning bins, 80 tons capacity each, will receive...

Jan 1, 1953

Central to any business is its Asset Management Plan which encapsulates the business context and key organisational objectives such as profitability, safety and environmental standards. Life Cycle Planning (LCP) is a key component of an overall Asset Management Plan. A comprehensive approach to Life Cycle Planning forecasts the financial expenditure required to support the performance of the asset over the business life. It incorporates capital, maintenance and operational expenditure along with an estimation of economic life. Within its body the LCP provides the detail of the maintenance plan and method of its execution. Once optimised the LCP becomes the overarching plan executed through the application of several elements of the Asset Management Plan to ensure the return on investment from the assets is optimal. Each of the elements of the LCP is bound by a set of loops that provide information based on the analysis of outcomes. These loops drive the continuous improvement of performance and cost over the life of the asset. In this way we ensure that the LCP is a dynamic plan responsive to the changing business environment. The paper being presented today will describe the process undertaken and the outcomes derived when this approach was applied to a $600 M+ coal handling and preparation plant in QueenslandÆs Bowen Basin. It will also delve into the difficulties encountered from both technical and cultural aspects; the latter proving to be the most difficult to manage. It will describe the hurdles and barriers that hampered progress including the human influences and the natural desire to revert to what has been done in the past when things became a bit difficult. In the end the results are there to show that the upfront expenditure and investment in time was time and money well spent and the outcome has the operation well placed to manage the assets in a manner designed to deliver the optimal business outcome.

Jan 1, 2007

By Baynes F. J, Bermingham A. G

The 6000m long King Headrace Tunnel will be driven through hard Owen Conglomerate in the Eastern third and feldspar porphyry in the Western two thirds, with the anticipated hardness up to 350MPa unconfined compressive strength. Since the Commission had not driven a long, large diameter tunnel for some twenty years, major research was undertaken to assess the current tunnelling trends. Tunnel boring machines were compared with drill and fire equipment. Rail equipment was compared with rubber tyred equipment. Tenders were called with tenderers invited to submit alternatives if desired. Commissioning and production excavation using the equipment is discussed with the final conclusion being that the individual items of equipment purchased combined to make an efficient hard rock drill and blast system capable of progressing through all rock conditions likely to be encountered on the King and Anthony Schemes.

Jan 1, 1987

In the last several years we have seen the demise of the Department of Mining and Metallurgy at the University of Melbourne, the removal of extraction metallurgy from the Department of Metallurgy and incorporation of it within a School of Mines at the University of New South Wales, and the joining of a small Department of Metallurgy with a Department of Chemical Engineering to form a Department of Chemical and Materials Engineering at the University of Newcastle. Most of these changes have been forced by the logical application of the principles of accounting, the currency for such accounting being the Whole Student Unit (WSU). It is not my intent to address the problem of attracting young people into courses in metallurgy (including extraction metallurgy) which, at present, is the only way to introduce black ink into the WSU accounting ledger. Rather, I wish to express my disquiet over the trends, illustrated by some of the above occurrences, of separating out extractive metallurgy from METALLURGY by suggesting in broad terms how a course in metallurgy should be structured. I firmly believe that the mechanical metallurgist and materials engineer need an exposure to chemical and extractive metallurgy; similarly, the extractive and process metallurgist should, in my view, have a good grounding in the interrelationships between composition, structure, and properties, this topic being the core of the basic subject physical metallurgy.

Jan 1, 1987