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By Roberts JD

The design and installation of a major on-line stores and purchasing system, with built-in maintenance reporting and plant register capabilities, needs more than just close attention to computer design details. When the system must be available almost 24 hours a day to a number of mine stores sites, and is used by a variety of mining staff including engineers and stores clerks, as well as by remote purchasing and office staff, then simplicity of use, availability, fast response times, and other human factors become vital. Critical aspects include easy to use screen design, involving a change from the traditional hierarchical menu system, and fallback and recovery to the last transaction. Business, people and systems objectives need to be established at the preliminary design stage, so that results can be measured and corrective action taken. The amount and type of user involvement and training, at all stages from initial design to systems tuning, has a major effect on people wanting to use the system. Active user participation in systems design, data definition and collection, and use of relevant training material is needed. Project management and design problems can arise in working with database oriented computer staff, and certain design features are found useful in ensuring a responsive, robust overall system.

Jan 1, 1983

Present value maximisation studies are a useful aid in enhancing the economic performance of open pit mining operations. Maximising present value helps to reduce the risk of financial failure. Maximisation of present value also means that the capital invested is being used most efficiently. A characteristic step in determining the present value of an open pit mining operation is to set out the sequence in which increments of material (ore of various grades and waste rock) are mined. Traditionally, present value maximisation has been performed by selecting a cut-off grade for each increment so as to maximise the present value of the total operation, by an iterative process using computers. Kenneth F Lane has developed a method and applied it to many mining operations. An alternative method for determining the maximum present value of an open pit mining operation is given. In this method the maximum present value is determined by working backwards from the end of the operation life, progressively asking the question of each increment `what cut-off grade maximises the the present value at the start of mining of that increment?' The method allows calculations to be performed by a `spreadsheet' package. Present value determinations are characteristically performed under constant conditions (eg prices, costs) throughout the operation life. Unfortunately real life circumstances are rarely constant, with the costs of mining inputs rising at variable rates. The prices received for mineral products have been shown to broadly trend downwards with time in real terms. Treatment of such changes in the determination of the maximum present value of an operation is discussed.

Jan 1, 1994

By M Kuruppu

The paper explores the sustainability of the Australian mining industry, and the potential for application of a substitute fuel into existing mining operations. This alternative fuel biodiesel is produced from biological oils and not from refined hydrocarbons like the transport fuel diesel (petrodiesel). The fuel is compatible with all current diesel equipment with little to no modification and has many superior properties. As biodiesel is derived from biological sources it is æcarbon neutralÆ meaning there is no net carbon addition to the atmosphere when the fuel is burned. The current fuel, petrodiesel releases long stored carbon dioxide (CO2) and is of concern to Australian government targets which seek to reduce these emissions. The mining industryÆs unique reliance on petrodiesel is of particular interest when assessing the substitution of biodiesel into underground and open cut operations. The underground benefits of biodiesel see a reduction in the noxious emissions of carbon monoxide and diesel particulate matter, both contaminants which require extensive diluting ventilation to ensure safe levels. As biodiesel is both safer to store due to its higher flash point and produces less exhaust emissions, its occupational health and safety benefits in underground mines is clear. The use of biodiesel in open cut mines benefits the environmental sustainability aspects of the project. The formulation of national targets relating to carbon dioxide emission reductions promotes any measure to reduce CO2 within the mining environment. As the diesel engine is one of the least emission efficient (kWh/tonne CO2) energy sources on-site, its potential for reduction in CO2 at minimal cost is the greatest. By substituting the fuel, significant quantities of site emissions are reduced, thereby achieving the goals of improved site sustainability and the governmentÆs targets to reduce emissions. This aspect of gauging mutually beneficial relationship regarding government interests and mining industry profitability is the underlying outcome for this paper.

Jan 1, 2009

By K Whelan

The Land Access Branch of the Mines Division of the Northern Territory Department of Mines and Energy is responsible for Aboriginal Liaison and cross-cultural matters that affect the Department. In essence, it exists to provide a basis for communication between the Department, industry. Aboriginal organisations and Traditional Owners. The paper outlines the various ways in which this is accomplished including the preparation of detriment submissions for pending land claim hearings, the use of promotional material to support access to Aboriginal Land for NTGS Mapping Programs and field work, and advice/assistance on exploration and mining issues.

Jan 1, 1994

By S Grano, J Ralston

Selective oxidation of minerals was used in this study to separate by flotation the copper sulphide minerals of chalcocite, covellite and chalcopyrite from the arsenic copper sulphide minerals of enargite and tennantite. It was found that a satisfactory separation of these minerals was only possible after selective oxidation of their surfaces in slightly acidic pH conditions, or after oxidation and selective dissolution of the surface oxidation products with a complexant in basic pH conditions.

Jan 1, 2000

By J P. Hsi

Recent increase in the development of underground space in urban areas in Australia has included soft ground tunnel construction. The ground movements associated with soft ground tunnel construction may present risk to other existing and proposed structures in the nearby vicinity. Much experience has been gained both in the UK and Asia in recent years in the engineering evaluation of this risk. The paper presents a procedure to assess these aspects of soft ground tunnel construction with reference to recent projects.

Jan 1, 1999

By Toffeg A. N, Abdul-Hameed I

More than 1000 Ian of seismic reflection data correlated to ten exploration wells along with geological, gravity and magnetic data are used to construct the subsurface structure, in particular the crystalline basement, along a corridor approximately 100 Ian wide that traverses central Iraq in SE-NW direction for a distance of about 500 km from Baghdad in the central part of Iraq to Dohuk near the Turkish border. This transect is one of few such transects that represents the Iraqi contribution to the Global Geoscience Transects (GGT) project. The transect crosses two out of three major tectonic elements of Iraq: the unfolded zone and the folded zone.

Jan 1, 1990

While international coal trading operations often involve relatively small contract quantities, delivered over short periods or even in single shipments, most coal is supplied under long term arrangements. In entering into these arrangements the customer needs to be assured that coal of suitable and consistent quality can be supplied for their duration in the volume required. A detailed knowledge of the mine and transport system is required and must be presented from the customer's perspective.

Jan 1, 1983

Hydrocyclones are widely used in both mining and various industrial sectors. Considerable fundamental research work on the modelling of hydrocyclone classifiers has been carried out through the past 25 years. Based on the similarity principle, the hydrocyclone classification was taken as a whole physical process and a group of similarity numbers were obtained with the help of dimensional analysis in this paper. Then, the functional dependences of the similarity numbers have been established. The variables optimisation was carried out with the multiple objectives linear planning programs developed in this study.

Jan 1, 1993

The accepting of the geologist as part of the mining industry team has only become a reality in the last fifty years in Australia. Commencing in the 1920's it received a check in its progress during World War II. Since then it has had its highs and lows to extremes not hitherto experienced. The recent mining boom and the succeeding slump have provided opportunity to examine more critically and positively the role of the geologist in the mining industry. The future is examined, not in crystal ball fashion, but in terms of selected specific aspects. Suggestions are offered concerning these aspects.

Jan 1, 1976

With the recent collapse in commodity prices the size and number of resources project has diminished markedly in recent years. Coupled with the disappearance of the "open cheque book approach", this has led to a revival of the lump sum or turn key project. The key features of this mode of development are compared with the "owner managed" and "reimbursable cost plus fee" alternatives - with respect to schedule, cost and quality control. Key facts for the successful implem- entation of this mode of development are identified. However, the approach is not advocated for all projects and the potential shortfalls are also identified.

Jan 1, 1986

In both surface and underground coal mines, the detection of geological structures ahead of workings is recognised as being fundamental to the efficient operation of the mine. Mining into zones of unexpected structures has a drastic effect on a mine's productivity. For the prediction of structures, geophysical methods can be applied from the air, from the ground surface, from boreholes and from underground workings. There are several improvements to report in the geophysical methods being developed for these purposes. These include developments in three-dimensional seismic reflection surveying, cross-hole seismic reflection methods and radar systems. The recent development of the radio imaging method for use in underground mine workings will complement existing in-seam seismic methods. Geophysical techniques for use in horizontal boreholes are also under development.

Jan 1, 1988

The scale and seriousness of AustraliaÆs social and environmental problems are no longer in doubt. We are consuming the opportunities of future Australian generations by our lifestyle choices. And at the global level, human activities are altering the very systems on which our species depends. Doing nothing about such problems as climate change is not an option. It is possible to move to a sustainable future but it will require fundamental changes to our values and national social institutions. We must recognise that we share a common future with the entire human family and the other species with which we share the planet. It is not just our humanitarian duty to improve the lot of the poorest people of the world. It is also enlightened self-interest because a world of increasing inequality will be a world of increasingly destructive tension.

Jan 1, 2004

By J Morton

There are many avenues for potential liability facing the Mining Industry today. Liability for breaches of environmental statutes such as the Resource Management Act 1991 and the Hazardous Substances and New Organisms Act 1997 include not only financial penalties but imprisonment and perhaps even more significantly will affect the reputation of the Industry. The potential for liability is not restricted to the employees that cause the actÆs to which liability attaches, but also potentially affects all the levels of management and even the company itself. There is also potential for liability through common law actions which can be utilised in cases of environmental harm. These should not be ignored by the Mining Industry. The Mining Industry must take a proactive approach to minimise exposure to potential environmental liability. This can be achieved by undertaking comprehensive environmental management initiatives and policies.

Jan 1, 2005

Australia has a long and successful record in mineral processing technology extending over 100 years. This has included the development of new processes and equipment and new analytical techniques. These developments have added greatly to the efficiency of mineral processing and thereby to Australia's national wealth. Demands on mineral processing engineers in the future show no signs of diminishing, in fact they will increase considerably as more difficult areas must be treated and the requirements for quality control become more stringent. These demands must be met successfully since mineral processing must continue to be one of the most important technologies in Australia's economic future.

Jan 1, 1989

By Equivar J, Mirabal C, Pyper R

In 1984, work was started to determine the viability of heap leaching silver-containing waste dumps from Cerro Rico near Potosi - Bolivia, at an elevation of 4300 meters (14 100 ft.). The result today is an unusual heap leach utilizing fine crushing, grinding, and agglomeration to process 1000 tonnes per day of ore containing 200 g/tonne silver. The unique metallurgi- cal, economic, and political factors will be discussed which led to the decision to build a heap leach rather than a conventional agitation leach plant. Capital and operating costs will be given along with some of the uncommon process design and equipment problems encountered while developing the operation.

Jan 1, 1991

By S R. Hencher

The development and availability of modern software for cavern design over recent years has provided design engineers with a range of usable design tools. The paper discusses the range of modern software available, presents a design methodology, reviews ground investigation requirements and software available for data processing and management, and discusses requirements and common analytical considerations with reference to typical packages. Caution is given of the tendency for readily available and user friendly software to be used without a full appreciation of the underlying engineering principles.

Jan 1, 1999

By Y Zhang

Being analysed systematically, the factors influencing the production of fully-mechanised coal face have been divided into geological, mining technical, and management groups. Artificial neural network-expert systems (ANN-ES) are established to decide the influencing factorsÆ membership grade; genetic algorithm-artificial neural network (GA-ANN) are used to decide the weights; fuzzy comprehensive evaluation method is used to calculate the integration indexes. Finally, the GA-ANN model is established to forecast the production of fullymechanised coal face. It is proved that the model is reliable with higher precision. The production of fully-mechanised coal face is influenced by many factors. However, some influencing factors are neglected by the traditional forecasting methods, the results of which are not precise and hardly be used as a guide for mine production and management. The relation between the production of fully-mechanised coal face and its effecting factors is analysed, and the meta-synthetic AI approaches are used to forecast the production of fully-mechanised coal face.

Jan 1, 2003

Inevitably the 'post-boom' era has changed the emphasis of many mining companies away from new project development and expansion to optimisation of existing operations. However, regardless of the project, high quality ore characterisation will remain of the utmost importance. In the case of new project development the need to understand the breakage characteristics will remain as important as it has always been. In optimisation projects, however, where it will be required to get the very best from existing comminution circuits, accurate geometallurgical modelling will take on an increasingly important role. However, these requirements, in both new development and optimisation projects, are likely to be at odds with budgets as these will be tight. Hence obtaining the best value for money will be essential. This paper discusses the elements that need to be satisfied for ore characterisation programs to be successful. Some of the issues covered will be: ore variability and sample selection, test precision, problems with the use of non-standard testing equipment, and the value of databases.

Jan 1, 2009

The Proterozoic Pb-Zn deposits of the Gulf of Carpentaria, Australia, include HYC (McArthur River), Mt. Isa, Dugald River, Lady Loretta and Hilton. Two seamingly incom- patible depositional models have been proposed to account for their origin. Finlow-Bates (1980), Large (1983) and Russell(1983) classify these-deposits as sediment-hosted submarine exhalative deposits. This class includes Rammelsberg, Meggen, Silvermines, Sullivan and others. In contrast, a lacus- trine, shallow-water origin has been advocated by Williams and Logan (1981), Logan and Williams (1984), Muir (1983) and Eugster (1985). The discrepancies between these two models can be removed by creating a separate class, that of continental sediment-hosted exhalative deposits.. HYC., Mt. Isa and Dugald belong to this class and their sediments were deposited in shallow, alkaline lakes. Metal- rich, hot, Na-Ca-Cl brines entered the basins along boundary faults and interacted with pore fluids and sediments, depositing-Cu-Zn-Pb sul- fides. Similar brines entered the Lady Loretta basin after marine flooding, depositing sulfi- des and barite, placing Lady Loretta into the class of marine Sedex deposits.

Jan 1, 1987