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By G Mulder, M Adams

Since the introduction of raiseboring 30 years ago there have been many operational and mechanical design improvements in the raiseboring machine, its reamers and associated cutters. These have now made the technology of raiseboring a routine and practical operation within the underground mining world. Over the last decade these advances have been aided by the introduction of robust automation packages which have allowed unattended drilling and reaming, real time performance monitoring and enhancement and the rapid diagnostic investigation of mechanical and electrical abnormalities. The constraint to higher raiseboring performance is now the drill string. However when it comes to a cost-effective solution of applying the high drill string torque and tension necessary for the next step change in performance, designers have æhit the wallÆ. Whilst carbon fiber reinforced plastic composites with abrasive resistant sheaths may offer a solution, the limit of conventional steel, drill string technology has been reached. This limit to advancement is however based on the drill string being in tension and alternative solutions may exist by literally turning the raiseboring paradigm on its head. This paper describes the story of a small Australian company engaged in the design and manufacture of mechanical excavation machines, two Australian raiseboring contractors and three Australian mines going against tradition and pushing down rather than pulling up.

Jan 1, 1998

The first thing to be aware of is that the warming effect of carbon dioxide is strongly logarithmic. Of the 3¦ that carbon dioxide contributes to the greenhouse effect, the first 20 ppm has a greater effect than the following 400 ppm. By the time we get to the current level of 384 ppm, each 100 ppm increment will produce only about 0.1¦ of warming. With atmospheric carbon dioxide rising at about 2 ppm per annum, temperature will rise at 0.1¦ every 50 years for the next couple of hundred years before the effect becomes minuscule. The warming of the 20th century, as the Earth came out of the Little Ice Age, was a consequence of short, high-amplitude solar cycles. A number of solar physicists have predicted that the next solar cycle, Solar Cycle 24, will be quite weak. Based on the correlation between solar activity and the EarthÆs climate, a temperature decline of 2¦C is predicted for the mid-latitude regions over the coming decade, equating to the experience of the Dalton Minimum. Anthropogenic warming due to carbon dioxide will not ameliorate this temperature decline. Increased atmospheric carbon dioxide is wholly beneficial due to itÆs fertilisation effect. Efforts to inhibit Australian carbon dioxide emissions are exactly wrong in science.

Jan 1, 2009

Because of the work of the pioneers of sampling theory, we know the principles, test work and equations to use to design sampling systems to meet targets for precision and accuracy. However, we do not see such æproperÆ systems deployed everywhere a sample is obtained around mineral processing plants. In many cases, we do not have solutions that satisfy all of the theoretical, economic and practical considerations. There are some well-known problems, such as high-volume streams with wide size distributions combined with a sparse valuable component that is heterogeneously distributed (such as gold ore SAG mill feeds). However, other difficult sampling issues are common, such as streams which vary widely over a day in flow rate and slurry density (many flotation concentrates), and loaded CIP carbon on transfer to elution. Inventory measurement issues abound, especially for leaching operations where daily inventory change is significant for metallurgical accounting. The result is that operators realise that although they issue reports daily, they do not know what is actually going on in their plant on a daily basis with sufficient confidence to quickly diagnose problems or confidently predict the benefits of potential enhancements. The industry needs practical and economic solutions that can be awarded the ætheoretically correct samplerÆ tick in order to better understand and optimise their processes.

Jan 1, 2008

Asian countries are now facing very crucial aspects of urban living under the recession of the economy. The current situation is such that those hard aspects may make the living standards worse and worse in the next century, unless proper measures are taken on the infrastructure for urban lives. More than half of the population in Asian countries are now living in cities. Nowadays, the socio-economic development of the Asian countries has been closely linked to the development of world economy because of the border-less economy system. The population inflow to big cities is inevitable as the Asian countries step into an industrialised economy. Such a tendency will be further accelerated when Asia becomes a centre of financial business in the 21st century. The government of any country has realised the situation very well. The United Nations has established a specific agency to solve the problems caused by the rapid urbanisation. This global agency for urbanisation is named United Nations Center for Human Settlement and it is so called Habitat. There are three Habitat offices in the world, Nairobi in Kenya, Santiago in Chile and Fukuoka in Japan. The activities of Habitat offices cover a wide field of issues such as housing, urban development, infrastructure and environment, etc. Habitat Fukuoka Office is serving Asia and Pacific in co-operation with the government offices concerned.

Jan 1, 1999

This paper considers the standard of ore reserve assessments required by lenders when presented to support requests for project based loans. The way lenders use this information to structure a suitable financial package shows why ore reserves should be measured by industry set standards. This in turn raises questions concerning the assumptions used to derive mineable reserves from geological reserves. Consideration of the variety of related problems highlights the need for assessments to be defined according to acceptable standards. These should also address the suitability of the methodology to the assumed configuration of the orebody; the degree of variance and relaibility of estimates of grade and tonnage presented; and the estimation of probability that ore will in practice fall within the defined limits. In an increasingly international marketplace it is appropriate to compare Australian industry requirements to those of similar overseas industries, in this case the United States. Lenders would like to see that individuals responsible for the preparation of ore reserve estimates are certified on the basis of their skill and expereince by an industry body such as The AusIMM. The paper discusses how each of the parameters indicated above may impact upon a lender's assessment of the viability of a project. A number of practical examples are presented where inaccuracies or inadequacies in ore reserve information have led to reduced project performance.

Jan 1, 1987

By Boyd G

Deep mining in the Collie Basin has suffered with high levels of water flow and sediment in-rushes throughout its 90 year history. Current day experience in working conventional bord and pillar by mainly mechanised means is that advance to the dip is impeded at about the 150m depth of cover by excessive water flow and pressure bursts. Extensive analysis of exploration borehole data and reconstruction of depositional environments helped define important hydrogeological characteristics of roof and floor aquifers, aquitards and aquicludes. Hydraulic parameters were estimated with some accuracy using indirect methods, and later confirmed by pump testing. Groundwater flow modelling showed that mine scheduling would have to be a balance between down dip and lateral development if aquifer pressure heads were to be decreased to suitable levels. Since pressure reduction in aquifers immediately above and below the mine opening was. identified as the key aim in groundwater control, a series of trial in-pit dewatering holes were installed, and demonstrated pressure heads could be reduced at rates compatible with a mine extraction sequence which, in turn, controlled the rate of down dip mine advance. A case history of the successful application of in-pit dewatering systems within difficult hydrological conditions for mining is described, with emphasis on the close collaboration required between hydrologists, mine planners and operations personnel.

Jan 1, 1988

This short paper outlines the authorÆs views regarding the progress we have made as an industry in managing mining assets over the past 500 years. It represents a personal view û but one founded in fact-based observations of mining companies and of the mining industry in general. There is no doubt that AgricolaÆs views as expressed in De Re Metallica (1556) were visionary. There is also little doubt regarding another issue û that whilst a great deal has been learnt about the management of mines since AgricolaÆs time, observations suggest that best practice management is the exception rather than the rule across our industry. Although insights regarding the successful management of mines have become apparent, we still witness unnecessary errors in our industry that lead to the loss of shareholdersÆ funds. By highlighting some aspects of current best practice, particularly in the arena of operations management, it is hoped that this short paper contributes a small step along the next 500-year-long learning curve. The paper concludes with a brief description of the progress and impact of continuous improvement initiatives at Kalgoorlie Consolidated Gold Mines (KCGM). Located in the Kalgoorlie Goldfields, KCGM is currently AustraliaÆs largest gold mine producing over 800 000 ounces of gold per annum. Improvement initiatives at KCGM look set to deliver some $100 million in value over life-of-mine.

Jan 1, 2004

By A Sellgren, M R. Carstens, R Visintainer

There is a wide variety of industrial pastes or non-settling slurries pumped in mining, dredging and reclamation projects as products, refuse and tails. The types and/or names of some of the common ones are alumina red mud, phosphate clays, tar sands mature fine tails, tar sands (CT) consolidated clays and fly ash. The pipeline performance or friction of these varies dramatically with the type, its concentration and the particulars of the actual slurry making it difficult to select pumping equipment and to design associated pipelines. The GIW Hydraulic Laboratory in Grovetown Georgia has tested a number of these slurries over the last 30 years for various mining customers. Where available in the public domain and/or where permission has been obtained, the results of those tests are presented in this paper in a form usable for pipeline and pump system designers and users.

Jan 1, 2005

By K Uchino, M Inoue

Self-potential anomalies are generated by fluid pressure gradient, by temperature gradient or by chemical gradient. On the basis of this principle, a new technique is proposed to locate the fire source of spontaneous combustion of coal by the self-potential method. In order to investigate whether this method can be applied to locate the spontaneous combustion of coal in practice, surveys of self-potential distributions were undertaken in a coal waste pile undergoing spontaneous combustion. The results showed that there is a negative centre of the electrical potential distribution in the measurement area. The potential in this centre is about 140 mV lower than that in the surrounding area. Moreover, the negative centre of electrical potential distribution almost overlaps with the high temperature zone. Therefore, it is concluded that it is possible to locate the heat source by the measurement of self-potential distribution.

Jan 1, 2005

By Henley S

The year 2000 is not very far ahead - only five years. It should not be hard to forecast what will happen between now and then, because the technologies that will be in practical use then should all be at least in embryo existence now. There has been a historical trend for the mining industry to work ever more difficult and ever more marginal deposits. There are clearly a few exceptions and major discoveries, but the industry is becoming heavily dependent, at both the exploration and the mining stages, on technological innovation to retain acceptable profit margins. With the new exploration and mining technologies come requirements for additional computing support. Computing technology further allows the potential integration of a wide variety of different types of data to help the explorationist to build and test exploration strategies, or to help the miner to design and schedule mining operations.

Jan 1, 1995

A philosophy is presented that new graduates in mining and metallurgy should be equipped to use computers during their under- graduate courses, should be aware of the capabilities and costs of a wide range of computing equipment, and should receive sufficient stimulus to become involved in applying computers for the benefit of the mineral industry. A program is presented in which computer applications and "hands on" involvement with computers are integrated into the progressive stages of the undergraduate courses in Mining and Metallurgy. In this respect, the role of the computer is to assist the student by performing time consuming tasks, to demonstrate the industrial applications of computing, to extend the scope and complexity of the tutorial, assignment and project work which can be undertaken by the student, and to provide the essential first stepping stones toward continued useful involvement with computers during the graduate's working life.

Jan 1, 1977

The theme of my address to your Institute, indeed its name, is "The Mineral Industry - What Next?" Knowing that I was required to make four appearances, and not wanting to be too repetitious, I wrote a rather long speech of which I will deliver various sections at different places, with a common introduction. Specific areas I have addressed are "Exploration", "New sources of minerals and energy", and "Mining and metallurgy of the future".

Jan 1, 1984

By Schulz R. S, Staunton W. P, McGuire J

The increased activity in the Australian gold industry over the last decade has resulted in a concomitant increase in the use of sodium cyanide, with a projected consumption of 80,000 tonnes per annum by 1991. Growing environmental awareness by government, industry and the public has generated increased interest in the fate of cyanide near gold mine tailings dams and has highlighted the lack of basic knowledge in this area, particularly for Australian conditions.

Jan 1, 1991

By Atkinson D

This paper briefly outlines the develop ment of the froth flotation plant at Coal Cliff Colliery. The plant was superimposed onto the original flow sheet in which fines were merely thickened and filtered. Test work leading up to the installation is described and the final layout is discussed. Details of the concentrate and tailings systems are given. Preliminary results of a further extension involving the use of a Davcra flotation machine are also given.

Jan 1, 1974

I have spent most of the past thirty-five years working as an economic geologist in the area of exploration and development of base and precious metals. Most of this period has been as an employee of Trans-National-Corporations (TNC's). I presently act as a consulting geologist to a joint venture company, bringing together two such TNC's: Anglo American' Corporation and affiliated companies De Beers (Diamonds) and Minorco (Metals mining outside of Southern Africa), and Normandy Mining Limited of Australia. Normandy is presently through its gold arm PosGold, Australia's largest gold miner and Anglo American can claim to be the world's largest gold company producing over 280 tonnes of gold a year, more than twice its nearest rival Gold Fields of South Africa. In addressing this topic, the role that Government can, and should play in mineral development, I will be drawing heavily on some examples from these and other TNC's experience in recent offshore mining Investment.

Jan 1, 1995

By Kershaw MG

At the Risdon plant of the Electrolytic Zinc Company of Australasia Limited, impurities toxic to the electrolytic production of zinc metal, notably arsenic and antimony, have traditionally been coprecipitated when precipitating iron as ferric hydroxide. With the development of a new lead/zinc mine at Elura, New South Wales, it was anticipated that the concentration of impurities, particularly arsenic, in the zinc sulphide concentrates treated at Risdon would increase. This suggested that an increase in the capacity of the iron purification step in the Risdon plant would be required to cope with the higher input of these impurities.Laboratory investigations showed that the additional capacity would be achieved, either by a massive increase in the amount of iron used as the "collector" in the process, or by a two-stage process. The latter approach was preferred as an increase in the amount of iron precipitated would lead to much higher operating costs and overloading of the existing equipment.

Jan 1, 1985

This case study reviews the Charters Towers vein systems for potential open-pittable bulk tonnage resources in' stockworks, horsetails or multiple vein systems. The review summarises district evaluation undertaken over the last 18. months before specific drill evaluations.Historical mining from Charters Towers includes in excess of six million ounces at head grades of one ounce per ton. A review and structural studies show most veins as simple, tight systems without significant horsetails or multiple sheeted systems. In addition the normal gold content of the pyritic selvages ('formation') is low and disseminated gold is virtually absent. Shoots are structurally controlled on vein/vein and vein/contact intersections. Historically high production vein systems are hosted by .,.t o of the younger granodiorite phases.Geometrically most veins dip shallowly (from 45¦ to as low as 200) in a north or easterly quadrant. Flat dips permit open cut exposure of considerable vein area at a favourable stripping ratio.

Jan 1, 1986

By P McCarthy

Despite significant advances in the platform technologies that could form part of a system of mine automation, the goal of full automation in most underground mining applications remains distant. This is because the industry developed these platform technologies to achieve local improvements in safety, machine and labour productivity, and asset utilisation, rather than to work towards a goal of a complete system of automation for general application in underground mines. This paper reviews the history and current state of automation in the underground mining industry and uses lessons learnt from the automobile and general manufacturing industries to gain insight into the opportunities and pitfalls in the complex and uncertain path to automation of underground mines. It also evaluates the relevance of the current drivers of interest in the industry. From this, we hope to engender an attainable vision of automation in underground mining and determine the best development path, process and timeline to achieve this vision.

Jan 1, 2008

The proponents of new mining projects always run the risk that their project is deemed to be not in the public interest. Nothing to be done here except to try and pick it earlyùit is, after all, the approvals process that is supposed to screen such projects out. But there is a second risk, about which much can be done: that inadequate or untimely information confuses the formal assessment of a project and the political context within which the decision is ultimately made. This is environmental impact assessment (EIA) process risk and it has become steadily greater in a changing world, where: miners have lost clout; public trust in institutions has declined; governments follow, as authority pyramids give way to spheres of influence; NGOs are asking the questions people want answered; and stakeholders have become the reference point. This new world deals harshly with yesterdayÆs methods. But it needs to be understood if principles and methods for managing EIA Process Risk are to be advanced.

Jan 1, 2003

As part of the response to the increased demand for products such as iron ore, coal and gold many resource companies have identified the need to develop strategies focused on attracting high demand professionals and retaining current employees in the business. Recent graduates are entering a time where they can expect high starting salaries, attractive benefits and lifestyle options. At the same time high work expectations and large demands on both personal and professional development will also be the norm. Some of the challenges faced may include high demands on performance, working with limited resources, long hours, and tackling unfamiliar areas of work with little guidance. However, managing your career and these challenges effectively can give you valuable experience in a short amount of time. By offering situations from my relatively short, yet active, career in the mining industry during these boom times I will raise some key points on how to best leverage your commodity and make the most of a bullish market.

Jan 1, 2006