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This paper reviews the use of MTU diesel engines in uses such as Off-Highway Vehicles, Rail traction, Generating Sets, Marine Propulsion and Defence Applications, and focuses on a central theme of maximum power in the minimum of space.

Jan 1, 1986

The source and origins of the hydrothermal fluid of orogenic, or quartz-vein lode-gold deposits remain uncertain and disputed: Resolution would likely have a significant affect on exploration strategy. The gold-carrying fluid is interpreted to be a low-salinity mixed aqueous-carbonic fluid of near ambient pH and redox state, that may be derived either magmatically through crystallisation of granites at depth in the crust or through metamorphic reactions in a range of rock types. Classic isotope and geochemical tracers of fluid source have not differentiated these possibilities and have produced conflicting conclusions. Mass balance calculations show that fluid composition will be modified by wallrock reaction between source and deposit, and tracers should not be expected to give clear indications of fluid source. Fluid oxidation state can also be modified along flow paths. Tracers should be interpreted with care and with view to possible modification. Modelling of full flow paths and examination of the hydrothermal histories of proposed source rocks may be alternative approaches to determining fluid source.

Jan 1, 2002

By Olden WH

A scheme is presented whereby the complexities of design and operation of a hydraulically powered coalmine support are modelled using the finite element method. This enables predictions to be made of the interaction of the support with its environment in a variety of operating conditions. The model is a two dimensional representation. The modelling scheme was applied in two case studies. In the first, the performance of a four leg support was uprated by increasing the front leg force. The finite element model enabled changes in overall support performance to be verified. In the second case study, the change in lateral force developed by a two leg support was assessed with changes in support operating height and floor foundation stiffness. The modelling scheme is capable of further development with the possibility of extending the model into three dimensions and the addition of control elements that would enable an actual mining sequence to be Represented.

Jan 1, 1992

By Skinner J, Brackenbury K

The AuPlus" Systems have been applied in the gold mining industry to achieve improved gold recoveries, faster leach kinetics and reduced cyanide consumptions. Calcium or hydrogen peroxide, collectively known as peroxygens, can be used. The choice depending on plant design and the nature of the ore. Laboratory test work and plant trials are included in this paper to illustrate the benefits of peroxygen usage in extractive gold metal- lurgy.

Jan 1, 1991

By R Brake

The Enterprise Mine Project (EMP) is being developed by Mount IsaMines Limited as the future source of copper ore at the Mt Isa miningand processing complex. Environmental engineering is one of the majortechnical challenges facing the project because of the depth of theorebodies, high virgin rock temperatures and hot ambient surfacetemperatures in summer. This paper discusses the engineering principles adopted by EMP to manage the risks associated with working in these adverse thermal conditions.

Jan 1, 1998

There was a time, in the memory of some here tonight, when the annual meeting of The Institute was a nostalgic occasion. Often, in the 1920s, there was comment on the decline of Australian mining and on the lack of new mineral discoveries. When some of our Presidents prayed then for a new Bendigo, and instead were given a Mount Isa, they were justifiably disappointed because of the vastly different capital requirements.In 1967 the mining picture is very different. The recent mining developments in Australia are certainly as important as several Bendigos and several Kalgoorlies. The mining industry in Australia has never been more dynamic than today (Table 1). And if we ask why it is so dynamic, the answer lies in the role which overseas capital is playing in the industry. The contribution of overseas capital should concern us not only because we are members of the mining and metallurgical profession, but also because we have a duty to make our profession contribute as much as possible to the well-being of Australians. It is not sufficient to argue that overseas capital is good for the mining industry; we must also examine whether it is good for the economy and the nation. In this context the current criticism of the inflow of overseas capital into Australian mining is useful, for it gives us an opportunity to see what has resulted from the inflow.In discussing this question I do not suggest that we emulate Captain Hancock, that legendary Moonta mine manager who, according to Oswald Pryor's cartoon, used to say to his miners: "When I say a thing is, it is, even if it isn't". The question can only be discussed on a factual basis; and I would submit that many of the important facts relating to overseas capital in our mining industry are often overlooked or ignored. I would further submit, on the basis of these facts, that Australia's present day mining industry has been largely built on overseas capital and that the overall benefits of that capital to Australia have been enormous.

Jan 1, 1967

Water is required as a key strategic resource in most mining and metallurgical processes and, in some countries, it has become a limiting supply for the development of mining activity. During the last years, mining industry efforts have been successfully focused on water use efficiency in the different processes. However, these efforts will not be sufficient to compensate for the growing demand of mining products and the decrease of ore grades. New efforts should be oriented to the search for alternative water supplies such as sea water, with or without desalinisation, or water harvesting. But to survive this growing pressure and to get a social licence to operate, the mining industry can also assume a proactive attitude and pursue a prominent role in water management at regional and local scale. This paper reviews some of these emerging issues, particularly in the context of the Chilean copper industry.

Jan 1, 2009

By D R. Swinbourne

In the recent past a number of smelting plants were commissioned in India to supply the rising demand by domestic steelworks for manganese-based ferroalloys, and they enjoyed cheap electric power and readily available high-grade manganese ore. Presently, the cost of electric power is much higher than in some neighbouring countries, there continues to be poor transport infrastructure and the prices of high-grade manganese ore have increased. Additionally, the Indian Government has opened its economy to the outside world, resulting in the import duties on ferroalloys being drastically reduced. In this paper the current situation in India will be detailed, the electric arc furnace and blast furnace smelting methods for ferroalloys compared and proposals for the construction of a new ferromanganese blast furnace in India outlined. The future of ferroalloy smelters in India will be assessed and actions which could be taken to improve their position discussed.

Jan 1, 2000

By B Shen

The Wambo Rail Spur located near Singleton, New South Wales, Australia, runs for approximately 14 km linking the Mt Thorley rail loop and the Wambo Coal Mine. The project involves a 260 m long tunnel in weathered sedimentary and intrusive materials. The tunnel has a low cover and runs under a main highway. This second paper on the project looks into one aspect of the tunnel in detail: the use of shotcrete arch as the primary support for part of the tunnel excavation. The use of shotcrete instead of steel arch, formulation of the material specification, construction sequencing, installation at the excavated face and material testing for verification related to this facet of the project will be discussed in this paper. The tunnel opened in April 2006, and two years on, we briefly reflect on the impact of this design decision on the overall project.

Jan 1, 2008

A new experimental procedure for determining the solids flux curve is detailed. The procedure is based on measuring the concentration at various heights of a bed of settled solids formed during a semi-continuous sedimentation test. Unlike conventional thickener area calculations, the test procedure demonstrates the dependence of the flux curve on the system feed flux. At a given feed flux, there was good agreement between the solids flux curve determined by the method and continuous sedimentation results. The widely used method of Kynch was found to be restricted to relatively high effective feed fluxes and consequently there was poor agreement with continuous tests at low feed fluxes. The flux curve determined by the method of Coe and Clevenger was invalid for all feed fluxes. A case study shows how the required thickener area would vary for a number of fine coal processing options.

Jan 1, 1989

By Brook W. H

The history of the reduction of iron from its ores is lost in antiquity. Archreologists state that man has practised it for over four thousand years. Until comparatively recent times charcoal was the principal reducing agent for making metallic iron from its various oxidised ores. Coke was first used by iron founders in England in 1619, and its use spread gradually throughout the civilised world from then onwards. Indeed, the destruction of forests to obtain the requisite charcoal made the iron founders, both in England and America, extremely unpopular, and this hampered the iron industry to a considerable extent, until coal provided the metallurgist with a new and better fuel--coke which is used by most pyro-metallurgists today. The transition from wood to coal products for iron smelting had a profound effect on the location of iron works. Particularly was this the case in America where, in the infancy of the industry, practically each of the early States had its own iron producers, but as coal and coke replaced charcoal, there came about a concentration of the iron and steel industry around the coking coal deposits, and so today there are huge steel plants clustered around the soft coal basins in Pennsylvania and Illinois.The development of the iron and steel industry in Australia, which is comparatively recent by world standards, has been cradled in the coal basins of New South Wales. The first steel works of any consequence in this country were built near Lithgow, close by the mines which produced the coal for coking.Incidentally, these works were rather unique in that the three essential materials for iron and steel manufacture-ore, coal, and limestone-were found virtually at the works' back door.When, in 1912, the location of the proposed steel works for The Broken Hill Pty. Co. Ltd. for smelting ore from Iron Knob in South Australia was considered, the site ultimately chosen was at Newcastle, almost on top of seams of satisfactory coking coal. One of the major factors which had determined the site of the steel works was the fact that, about 1912, three tons of coal were required to produce one ton of finished steel product, and the relative economics of ore and coal haulage were much in favour of bringing ore to the coal.

Jan 1, 1947

By Bailey DJ

Loader cut and fill stoping was first used at New Broken Hill Consolidated Limited mine in 1966. The equipment used included single boom pneumatic jumbos for drilling up- holes, diesel loaders for ore removal and diesel utility vehicles for rockbolting and servicing. Since 1966, there have been many modifi- cations and changes both in the equipment and stoping method. Twin boom pneumatic or hy- draulic drilling jumbos have replaced single boom pneumatic jumbos, electric loaders have replaced diesel loaders, diesel forklifts have replaced utility vehicles and "'flatbacking" has superseded uphole stoping. Concurrent with this has been the introduction of cable dowels in stope backs which has enabled loader cut and fill stoping to be used more extensiv- ely than in the past. There are now six loader cut and fill stopes at both mines and this paper traces the evolution of this method outlining the reasons for changes in technique and equipment.

Jan 1, 1982

The Mining Act (1992) and the Petroleum Act (1980) provide for the Government of Papua New Guinea (PNG) to take up equity holdings in mining and petroleum projects. The price the Government pays for its share is based on the historical cost of exploration and development on the project to the date of government equity acquisition. The equity level to be acquired is not fixed and ranges up to 30o for mining and up to 22.5s for petroleum at the discretion of the Government of the time.The objective of this paper is to examine the pros and cons of State equity holdings in PNG from the point of view of both the State and the developer. Using an economic model of the PNG mining taxation system an assessment is made of the effective return on investment received by the State from such equity holdings. The results are compared with government revenues from other taxation measures.

Jan 1, 1994

Maintaining and improving the economics of open pit mining in the future requires understanding of the characteristics of open pit mining that are different to other mining or business activities, designing mines in the first place to be less susceptible to changes in these important characteristics, and adopting strategies which yield reliable returns despite unforeseen change. Planning and production personnel require guidelines and performance standards that are based on sound economics not solely on production criteria. The guidelines adopted for long-term implementation must assume a declining price for mineral products along with declining real costs, with research efforts directed at development of both evolutionary and revolutionary ideas aimed at implementation. Decision-making must focus on risk and probability criteria rather than just simple return-on-investment criteria, and the approach for management of personnel must support the higher level of communication essential for fast decision-making in the new environment of continual change.

Jan 1, 1992

In November, 1967, a four strand curved mould continuous casting machine coupled with a 50 ton basic oxygen furnace began producing billets for the rod mill and new merchant mill at the Newcastle Steelworks. To date over 500,000 tons of carbon and alloy steels have been cast at the rate of 20,000 tons per month, the major part for the wire industry. Many alterations have been made to the plant to simplify the process, improve quality and increase production. Casting parameters have been developed for each different type of steel. The quality of the final product has been influenced most by casting temperature, secondary cooling and casting speed. All these factors have been controlled and good results are reproduced. More exacting requirements of liquid steel quality have brought about the use of higher lime/silica ratio slags during steelmaking to control phosphorus revers- ions and standard ladle additions of manganese suicide and ferro aluminium for more effective deoxidation.

Jan 1, 1972

Mineral exploration conducted over a wide area of the State during the period 1960 to 1973 has resulted in the discovery of a number of significant deposits. Base metals, particularly copper, have been of prime interest while, more recently, the search for uranium and coal have assumed import- ance. Expenditure of $27.6 million by companies during the period under re- view has located 580,000 tonnes of cop- per, 370,000 tonnes of zinc, 350,000 tonnes of lead, 24 million Kg of uran- ium oxide and 2,500 million tonnes of coal. A variety of other metals and non metallic and industrial minerals have been investigated in a diversity of geological environments.

Jan 1, 1975

By Just G. D

Performance of draglines in large scale overburden stripping operations is critical to the efficiency of a major section of the Australian Coal Mining Industry. Optimisation of dragline productivity requires an understanding of a range of operating conditions and constraints. One of the least understood of these operations is the process of bucket filling and how this may vary with respect to variable operating conditions.Studies conducted at The University of Queensland over a number of years into this problem have enabled the mechanics of excavating to be assessed for different types of fragmented rock. In relation to bucket filling, factors such as fill volume, digging time and energy consumption have been found to be significant factors in optimising bucket design, bucket rigging and operational techniques.

Jan 1, 1992

By A Nixon

The Australian mining industry has changed dramatically over the past 20 years in terms of mining methods, mining equipment and human resource policies. The industryÆs approach to safety and health in terms of attitudes, style of legislation, and risk management techniques has also changed significantly. These changes have had and continue to have major impacts on the design of underground mine ventilation systems. In some areas, trends are clearly emerging. In other areas, mine ventilation planning remains very æreactiveÆ and is performing poorly in terms of providing a safe and healthy work environment at a reasonable cost. New concepts involving the role of ramps and shafts, the provision of refrigerated air, æventilation on demandÆ and newe gress and entrapment approaches are likely to be incorporated into mine planning and operating practices over the next ten years. This paper discusses these and other trends and identifies some likely future developments in the area of hardrock mine ventilation.

Jan 1, 2005

The global recession of the 1980s drove commodity prices down and intensified cost competition. The 1990s saw a restructuring of the mining industry with the survivors adopting new technology, significantly increasing workplace productivity and reducing capital and operating costs. Major changes in mining industry business strategies evolved in the late-1980s including the development of miner - supplier - manufacturer - partnerships, cultural changes in work practices and common goals between the partners to reduce the cost of production. These industry trends are putting new demands on mining machine manufacturers and dealers both on the `hard' side of the machine business, such as research and product development programs, and on the `soft' side in terms of business processes, use of human resources and communication. The paper describes several mining industry trends as identified by a large supplier to the industry, and discusses the impact they are having, and will have, on mining machine development and the provision of product support services to the industry.

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