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Self Advancing or "Poweredtt supports are a successful means of supporting roof and designs have reached the stage where adequate support capa- bility is available for all conditions. Some designs have resulted in equipment being too difficult to transport underground and too complex to maintain. Current trends are reducing those problems and simplicity in hydraulic systems is now the keynote of both supplier and user. There is a good possibility that the "Shield-Chock" support will be the universal design of the future. So-called t'shortwall supports" have been developed to the point where they can be applied with a high degree of confidence to conditions of great variety. Develop- ments by manufacturers and practices of users related to maintenance should result in consistent achievement of designed performance.

Jan 1, 1974

Economic evaluations of mineral projects are based on discounted cash flow analyses, followed by sensitivity and risk analyses. However, the global macroeconomic and political environment in which the mineral industries operate have a profound effect on the viability of individual projects. Since the oil crises of 1974 and 1980, demand patterns for minerals have become much more variable and prices more volatile. Significant changes in the geographical distribution of world mineral supply and demand are underway, and the mix of minerals used is also changing. Social and political factors are as important as economic and technical factors in determining the viability of mineral ventures. Economic evaluation of mineral projects have to be undertaken in a more uncertain and risky environment. They can no longer be reduced to a number crunching exercise.

Jan 1, 1987

The company was formed in 1926 to exploit tin bearing veins adjacent to Aberfoyle Creek in north-east Tasmania. In 1928 a 923ft tunnel was driven to explore and develop the mine 150ft below surface. This put the company on a path to become Australia's second largest tin producer by the late 1960's. Recently, Aberfoyle Resources Limited completed a 1.1km tunnel to access the major Hellyer zinc, silver, lead orebody at 300m depth. Production at 1 million tonnes a year is likely, and will make the company a significant world supplier of zinc by the late 1980's. The intervening 20 year history of survival and diversification illustrates principles of mineral exploration which proved valid in the Australian context. The objective of exploration should be to develop mines which can survive rigorous competition and downturns in commodity prices. Such mines will be based on orebodies with many of the following characteristics described by Richards (1986).

Jan 1, 1987

The role of marketing in the development of a new project will be affected by political, commercial and technical pressures. Marketing success will be determined by the ability to predict and react to tomorrow's environment. In the Australian coal industry there is an emerging transition from production to marketing orientation. As a result, greater technical awareness of customer needs will be required. In particular, the industrial product nature of coal markets will need to be recognised. Greater attention will also need to be paid to product options and quality in mine planning. Marketing personnel will become more involved at every phase of the development of a new mine.

Jan 1, 1983

The passage of a vast array of new State and Federal environmental legislation over the last couple of years has required many mine operators to sharpen their focus on environmental requirements. Established requirements, such as environmental impact assessment, minimising disturbance and rehabilitation must now be complemented by mine environmental management plans. These may not only require regular monitoring of mine operations and detailed forward planning to prevent or reduce environmental harm caused during mine operation, but annual updating. It is likely that in future these plans will be required to incorporate general principles such as pollution prevention, sustainable development, waste minimisation and conservation of biodiversity and ecological integrity.

Jan 1, 1993

The mineral sands industry in Australia can contribute much more sig- nificantly to economic development beyond the year 2000 by increased production of constituent minerals such as ilmenite, zircon, rutile, leu- coxene and monazite from existing and new resources, and especially from downstream processing to intermediate and finished products based on these resources. The end-use areas for mineral sand-based products include those products whose demand is tied to general economic growth, such as paints and plastics, and refractory bricks for the steel industry. High techno- logy applications such as zirconia ceramics and super-magnets are indica- tive of new developments in technology which provide considerable scope for expansion at higher rates than overall western world economic growth. An optimistic outlook for the industry is outlined, based upon a brief review of opportunities.

Jan 1, 1988

A programme began in 1970 to eliminate the charging of fine materials into the copper blast furnace of The Electrolytic Refining and Smelting Company of Australia Ltd. at Port Kembla, N.S.W. A disc pelletiser and drying plant has been installed as part of this programme. Feed material for the plant is a blended mixture of copper concentrates, fine copper-bearing residues, and blast furnace cyclone dust. The operating parameters for the disc have been calculated by comparing the perform- ance of three other discs on the plant. Re- search work on choice of binder, feed moisture and drying conditions has led to the production of reasonably high strength pellets. A description of the pellet plant and modifications necessary to overcome the initial performance problems is given.

Jan 1, 1974

By X Li, H Alehossein

The oscillating disc cutter (ODC) is an innovative technology for the continuous excavation of hard rock. This paper will discuss:the reasons for its development;its method of operation;current experimental results and mathematical modelling undertaken at the CMTE; andapplications in the mining and rock excavation industry.

Jan 1, 1999

By M L. Habner, S D. Munro

In a gold CIP/CIL circuit, adding new circuit water to a final tails thickener and then directing the thickener overflow to the head of the circuit significantly reduces the cyanide concentration at the TSF discharge spigot. The new water is used to dilute the final tails. The dilution and recycle of the tails in this manner may have the added benefit of reducing reagent consumption, in some cases to the point where the reagent savings justify the expenditure and Cyanide Code compliance is achieved at no extra cost. Potential circuit configurations and water recycles can be modelled by splicing a flowsheeting and thermodynamics package, such that changes to the composition of the water can be reduced to chemical speciation with a Gibbs free energy minimisation enabling a complete understanding of the circuit water chemistry.

Jan 1, 2007

The paper describes some of the economic and human factors associated with haulroads on Mount Whaleback, a large open pit iron ore mine. These factors have combined to encourage formation of a specialised road maintenance crew which caters for haulroad construction and maintenance. Techniques used for design, construction, operation and management of haulroads are then described. Future developments are expected to effectively lower construction costs leading to an even wider application of the techniques described and consequent improvement in temp- orary roads and overall truck performance. INTRODUCTION Mount Whaleback is a large truck/shovel open pit iron ore mine located in the Pilbara region of north Western Australia. Annual production capacity exceeds 100 million tonnes per annum of waste and ore. The truck haulage fleet comprises WABCO 120 52 WABCO 3200 22 74 of which approximately 45 are operating at one time.

Jan 1, 1982

Because the Australian resource industry differs from the resource industries of other countries, direct application of manpower planning processes derived from overseas experience may be singularly inappropriate for Australian projects. Too often in Australia, project manpower planning has been undertaken as an afterthought to technical and financial analysis. A wide variety of complex and interrelated manpower considerations should be evaluated from the beginning of project planning, even at feasibility study stage, and relevant deductions should be incorporated into all other planning. Many manpower factors can be considered sequentially but it is probably necessary to undertake critical path analysis for manpower planning. The paper highlights some key factors involved in project manpower planning and suggests a simple linear planning sequence which integrates the analysis of factors and can in turn be integrated into technical and financial planning.

Jan 1, 1983

Grinding is probably the single unit operation that requires the largest capital investment and operating costs in an ore beneficiation plant. Because of that, a great deal of research has been concentrated in the theory, design and operation of grinding equipment, in particular ball mills. To-date, the models developed to describe grinding in tubular mills are macrophenomenological and can be divided into two categories: energetic and kinetic models. This paper presents a new approach to modelling ball mill grinding: The Operational Model. The theoretical aspects of the model as well as a comparison with existing ones are discussed. The concepts of the model, summarised in easy-to-operate PC programs, permit the calculation and design of new ball mills, and a critical evaluation and optimising of mills in operation.

Jan 1, 1993

By K Inoue

The pressure oxidation of molybdenite concentrates in acidic and alkaline media has been studied. The conditions of the selective oxidation of copper and iron sulphide minerals with a quantitative copper leaching by ferrous-ferric-sulphate solution have been found and explained from the point of view of electrochemical kinetics. The partly oxidised residue consisting of molybdenite and (hydro-) oxide of iron (III) was then decomposed by oxygen in alkaline media. Effects of the main parameters, such us oxygen pressure, leaching temperature, solid-liquid phase ratio, autoclave stirring speed as well as lixiviants nature on the molybdenite oxidation rate have been established.

Jan 1, 2000

The value derived by good mine planning is often underestimated as many mines steer their attention to the more immediate and more easily recognised successes made by the day-to-day operational æbush fireÆ fighting. Similar to machine maintenance, the efforts made to quickly rectify short-term breakdowns are well recognised; whereas the value derived from the work in planning, scheduling and undertaking preventative maintenance is not so obvious or readily quantified. Too often the focus of the business shifts to building and supporting an efficient operations team at the expense of developing a highly experienced team of mine planning practitioners that are well trained with procedures and purpose-built tools to develop optimum mining strategies. A resource has an inherent value based on its quality parameters and its likely mining conditions. How well that value can be unlocked is governed, to a large degree, by the proficiency of the mine planning practitioners, as they, essentially, set the foundation of the mine business and the path along which the mine will operate. The importance of having a well documented and procedural mine planning methodology that integrates both a thorough technical and economic understanding of the resource cannot be over emphasised. The aim of the mine planning process is to develop a robust mine design and production capability which can best cater for future uncertainty whilst providing the best opportunity to maximise cash flow into the business. The planning process must be transparent and auditable, clearly summarising the process steps and assumptions made to arrive at a justifiable and defendable outcome. To provide maximum value to the business, the planning process must be repeatable and scalable to enable easy replication throughout the different mines and projects within an organisation. The diminishing numbers of highly experienced personnel within our industry, coupled with the growing pressure to clearly demonstrate that appropriate due diligence has been exercised, means that well documented and monitored mine planning processes using purposed built and innovative tools need to be developed to ensure optimum outcomes.

Jan 1, 2009

By M H. Randell, J B. Haines

The Honeymoon Uranium Project comprises the Honeymoon Deposit,Goulds Dam Deposit and Yarramba Prospect in the Southern Lake Fromeregion, South Australia. Both the Yarramba Prospect and HoneymoonDeposit (which includes Honeymoon and East Kalkaroo orebodies) arelocated in the Yarramba Palaeovalley. The Goulds Dam Deposit is about75 km north west of Honeymoon, in the Billeroo Palaeovalley. Exploration for sediment-hosted uranium began in the area in the late1960s, culminating in the discovery of Honeymoon and Goulds Dam inthe early 1970s. In 1982, a 25 L/s demonstration plant was built atHoneymoon to confirm suitability for in situ leaching. The project was put on hold in 1983 due to changes in government policy. Southern Cross Resources Australia Pty Ltd acquired the project in mid 1997. Roll-front deposits form from a migrating geochemical cell, anadvancing reduction-oxidation interface between oxygenateduranium-bearing groundwater and its reduced aquifer host. The source of metal is uranium-anomalous granites, which were eroded fromsurrounding ranges. The weathered granites and resultant sediments are stripped of uranium by oxidised groundwaters, to form solutions carrying uranyl carbonate complexes. The solutions percolate down-slope through permeable sand zones until contacting a reduced environment where uranium precipitates. Uranium mineralisation occurs interstitially between and as thin coatings on sand grains, usually in the form of uraninite or coffinite. The palaeovalleys (previously termed palaeochannels) are incised intounderlying Cambrian/Precambrian basement rocks and filled withsemi-consolidated, largely un-cemented, Tertiary sediments of the Eyre Formation. The late Palaeocene to middle Eocene Eyre Formation is the basal unit of the Tertiary succession in the Callabonna Sub-basin of the Lake Eyre Basin. Further to the north, the Lake Eyre Basin overlies the Jurassic-Cretaceous Eromanga Basin, which comprises much of the Great Australian Basin. Eyre Formation sediments are in turn overlain by the late Tertiary Namba Formation and terrestrial Quaternary units. At Honeymoon, the Eyre Formation includes immature, pyritic,carbonaceous sands and gravels interbedded with lignite andkaolinite-illite-montmorillonite clays. It was deposited by braidedstreams during epeirogenic uplift of the Olary Ranges, accompanied bysubsidence of the Lake Eyre Basin. The Eyre Formation comprises aconsistent stratigraphy of interbedded sand and clay units that arecontinuous over the Honeymoon Deposit but with local variationindicating some hydrological connection between aquifers.In the Honeymoon orebody, uranium occurs within coarse-grained,pyritic sands where the basal sand pinches out between overlyingcarbonaceous clay and the southern palaeovalley slope. Its characteristics are typical of the well-developed, planar limb of a roll-front uranium deposit. Zonal changes related to the reduction-oxidation interfaces across the deposit are readily observable. The orebody extends for nearly 1000 m along the valley margin, is 400 m wide at its maximum and averages about 6 m in thickness. The East Kalkaroo orebody also lies near the southern margin of theYarramba Palaeovalley. It extends discontinuously for approximately 3.5 km and averages 200 m width, with significant uranium present in the Middle as well as the Basal Member. The Billeroo Palaeovalley extends northward for 40 km sub-parallel tothe western side of the Benagerie Ridge, is up to 5 km wide and hasgently dipping banks. Eyre Formation within the palaeovalley isconcealed beneath 90 m of Quaternary and Namba cover, isapproximately 40 m thick, and is sub-divided into three upward-finingunits, which are remarkably similar to the Yarramba Palaeovalleysequence.

Jan 1, 2001

By Lee G, Stitt P

The term "industrial minerals" covers a vary wide field. However in Australia this field tends to be characterised by the follow- ing: (1) Relatively low unit values. (2) Product specifications can be exacting compared to the metalliferous field. (3) Product specifications often have to be tailored to the needs of the end user. (4) Beneficiation plants tend to involve low capital outlays relative to the metalliferous field. However they often have to produce products'to a range of specifications. (5) Technology often influences what can be considered as reserves. (6) Because of low unit values industrial minerals tend to be relatively cost sensitive. This is particularly the case in regard to transport. (7) Location of deposits near to major urban areas (markets) dictates a greater pressure on ecological aspects. (8) In Australia there has been a tendency to vertical integration largely due to the restricted market available. Reserves assessment is shown to be critically dependent upon the above Factors.

Jan 1, 1979

By Hughes A

Nchanga Division of ZCCM has installed and operated a trolley assist system on part of their truck fleet for some three years. This paper examines how the system came to be chosen and how the many features of construction and operation were dealt with. The economics and productivity of the system are presented as are the personnel aspects of acceptance and training. Zambia Consolidated Copper Mines is a state controlled copper mining company formed by the amalgamation of the former Nchanga Consolidated Copper Mines and Roan Copper Mines. The company operates seven copper mines the largest producer being the Nchanga division, which is scheduled to produce some forty-two percent of Zambia's copper production. The division operates four open pits and an underground mine which produce annually some 192 000 and 96 000 tonnes respectively of copper contained in ore.

Jan 1, 1986

The prospect of utilization of phosphate ores which contain high P205 values associated with Al and Fe has produced a great deal of interest over many years. Processing options have generally been based on the utilization of by-products which were required to offset the processing costs.This paper presents a range of processing options which have been investigated at laboratory or technical scale on phosphate ores which predominantly consist of crandallite, CaA13(PO4)2(OH)5.3H20 and millisite, Ca(NaK)Al6(PO4)4(OH)9.3H20. Christmas Island (Indian Ocean) and Mt. Weld (Western Australia) phosphate ores are good examples of such feedstocks. It is expected that these processes may also be applicable to such phosphate ores from other locations.

Jan 1, 1990

By Grainger A, Dawkins G, Lysaght A, Kennedy R

Maintenance management improvement projects were undertaken at several BHP Collieries Division mines pursuing.the objective of achieving better structured maintenance procedures. Efficiently structured maintenance and optimum asset use are interdependent and productivity and computer models assist towards that objective. Definition of aspects of maintenance and analysis of the nature of equipment and materials, workloads and tasks, lead to more effective planning and scheduling of maintenance. The quality, standards and procedures of records must be suitable and adequate for storage and future retrieval. Total Quality Control initiatives and improvement projects even extend into spheres of customer/supplier relationships and problem solving teams as well as the more recognisable standards of management and performance factors in maintenance. All such factors contribute to a Maintenance Management Matrix to provide a better structured approach to economic maintenance management in the capital intensive coal mining industry.

Jan 1, 1991

By Van Nostrand J

The resettlement and relocation program that is being carried out at Gold Fields Ghana's (GFG's) Tarkwa Mine is currently the largest of its kind in Ghana, and West Africa as a whole. While such projects have been initiated previously in Ghana, in connection with the development of the Volta River Dam, Tema, and a number of other smaller resource development projects, they were not subject to the statutory requirements of Ghana's relatively new Environmental Protection Agency (EPA). Nor were they subjected to the kind of global scrutiny that is now being applied to such projects by international agencies like the World Bank. This is a result of the international community's criticism of major energy projects like the Three Gonges Dam in China and a number of similar hydro-electric projects in Southern Asia. It has meant that for this project the expectations are considerably more challenging then they have been in the past.

Jan 1, 1997