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By B Goebel, G Baker

The Australian Magnesium Corporation Limited (AMC) is constructing the worldÆs largest magnesium metal plant at Stanwell, 24 km west of Rockhampton in Central Queensland. The $1.3 billion, 97 000 tonne per year plant is scheduled to commence production in mid-2004. It will produce magnesium from magnesite using the innovative, locally developed AM Process Technology which enables magnesium to be produced at internationally competitive costs. The technology will enable the plant to have the lowest environmental impact of all the available magnesium production processes. The project will meet current world-best-practice environmental and emission standards while on a life cycle analysis, magnesium produced by the Stanwell plant will result in net reduction in global greenhouse gas emissions. Magnesium is the lightest of the structural metals. Its high strength to weight ratio and ease of casting and machinability makes it particularly suitable for the manufacture of light weight automotive components. Reducing the weight of motor vehicles through the use of light weight materials such as magnesium is the current primary means adopted by the automobile manufacturing industry to improve motor vehicle fuel efficiency and the lowering of emissions of greenhouse gases. The Australian Magnesium or AM process has been developed over the past decade by AMC in conjunction with the CSIRO to produce magnesium from magnesite mined at AMCÆs Kunwarara deposit. Over $200 million has been spent developing the AM process, designing, building and operating a demonstration plant at Gladstone and to complete an environmental impact statement and receive environmental approvals as well as funding for the commercial Stanwell Project. The paper outlines the development of the AM process technology, the operations of the Gladstone demonstration plant confirming the process technology, its operating costs and environmental performance. The paper covers the particular attention that was given to minimising the production of CHCÆs, the development of new cover gases for molten magnesium, the minimising of emissions of greenhouse gases and the life cycle analysis of magnesium as a replacement for steel and heavier metals in motor vehicles which confirmed its use resulted in a net reduction in global greenhouse gas emissions. The project received both Commonwealth and Queensland Government environmental approvals by August 2000.

Jan 1, 2002

By Tenorio J. A, Vieira C. B, Sobrinho P. J N

This paper shows a review of bibliography and actual situation of the plastics injection into blast furnace. Some information about results and experimental practice with plastics waste are presented as well as the development of the injection plastics's technique.

Jan 1, 1999

By Kelly BJ, Smith GA

The recommendations of a recent American report on "Better contracting for Underground Construction" are considered in relation to Contracting practices on major Australian projects by representatives Of the "classical trilogy" - the Owner, Engineer and Contractor.

Jan 1, 1976

When a fire or explosion occurs underground the ventilation maybe disrupted and the atmos- phere may become oxygen deficient and filled with noxious and flammable gases. The basic survival technique for:any man alive underground is to escape and this may be achieved and rescue workers may enter such atmospheres to carry out rescue work underground by using appropriate breathing apparatus.

Jan 1, 1983

A unique set of circumstances has devel oped in the Mt. Newman Mining Co. Pty. Limited's project in the Pilbara because the mining town of Newman was built almost entirely by the Company whereas residential areas built by the Company at Port Hedland were developed as an adjunct to an existing town. The following discussion points out the different problems which have been developed in the two areas, even though basically the stand- ard of housing and general amenities is the same, and the means taken to overcome these Problems.

Jan 1, 1973

Synthetic hollow microspheres have demonstrated reliable sensitization and detonation characteristics in industrial explosives for almost two decades. During that time, water gel formulations and use conditions have changed. The introduction of emulsion explosives has also dictated technical improvements in microsphere sensitizers. In contrast to microspheres, gassing or other sensitizing techniques often cannot satisfy the manufacturing and blasting characteristics required of today's explosives. This paper discusses the sensitizing properties of microspheres, formulating guidelines and quality considerations. Packaging, sampling, transfer, metering, mixing and pumping information is also provided.

Jan 1, 1990

In conjunction with a study on wear of drag bits the effect of clearance angle on penetration rate was studied.Increases in clearance angle from 24 1/2 up to 30° gave an increase in penetration rate. Thereafter the rate was apparently affected by partial clogging with cuttings.Analysis of results was by a linear regression model and the t-test was applied to assess the significance of parameters in the penetration equation.

Jan 1, 1969

Predictive chemical models facilitate the selection, design and assessment of aqueous chemical processes. The development of expertise in aqueous themochemistry has not matched the explosion in computer technology for modelling, which has placed pressure on the need for acquisition of skills to critically assess the appropriateness of the models produced. The 'blind faith' culture which appears to be developing must be arrested by appropriate programs at the tertiary level and professional development strategies in the minerals industry.

Jan 1, 1996

The Plant Control and Data Logging System for the Loy Yang Open Cut (LYOC) is part of a control and communications network designed to provide a high level of surveillance of open cut plant and facilitate the efficient co- ordination of operations and plant maintenance. The computer system selected utilises a central dual mini-computer and multiple microcomputer data transmission network ,linked to the plant controllers using distributed, microcomputer based remote data collectors or outstations. Several aspects of the computer system are outlined.

Jan 1, 1982

By Burchell S, McGregor K

The process of design, measurement and review is essential if blasting is to continuously improve to meet the increasing productivity goals of most mining operations. To achieve continual improvements, many operators are turning to contractors to provide the necessary technology. Under this arrangement, the contractor becomes the supplier of a service rather than products and assumes some of the risks associated with blasting by guaranteeing the end result. If contractors are to obtain significant productivity improvements they must continuously improve every aspect of their business.

Jan 1, 1994

Capital expenditure on sampling and blending is often very difficult to justify. The costs are easy to estimate but the benefits likely to be obtained by constructing good sampling and blending facilities are generally difficult to estimate. For instance, improving blending of the ore feed to a smelter would improve throughput, yield and controllability ... but by how much? Similarly, better sampling would allow processing conditions to be dynamically adjusted and would improve extraction ... but by how much? Predicting benefits often requires the use of simulation models which carefully distinguish between true grades, predicted grades and observed grades. The parameters of these simulation models must often be estimated from rather inadequate information. These difficulties are illustrated using three scenarios.

Jan 1, 2005

There are a number a stages in a project at which an audit must, or should, be undertaken. An independent audit may be necessary for the comfort of directors and/or financiers before the major finance is committed, but an internal pre-development audit is the opportunity for the management team to take stock of the project and reaffirm their confidence and commitment. Maxims for project success are given and a check list for pre-development audits is presented. The need of mid-development audits may arise and their brief will depend on the circumstances arising. A game theory approach to decision-making is demonstrated in which the alternative of fast-tracking a development is considered. At the conclusion of the project, before the team is disbanded, a post-development audit should be made. Valuable learning can come from this process which could give important guidelines for future projects and a check list is presented.

Jan 1, 1997

The various risk components to be addressed by explorers and project developers (and their investors) to minimise and/or manage the risk of Pacrim mineral investment are summarised to provide an overview of the issues involved and to set the scene. It then highlights the role of individual Mineral Industry Professionals (especially independent consultants) who are at the heart of any risk reduction or risk management strategy. The involvement of accredited qualified/experienced (competent) and reputable professionals is essential to produce realistic and reliable results that gain and maintain investor confidence. Today, high ethical standards as well as technical competence are sought by government legislation/licensing regimes and initiatives of professional bodies like AusIMM, MICA, Professions Australia, Council of Professions, etc. All attempt to regulate and guarantee reputable individual professional behaviour (particularly in the context of currently perceived high corruption levels in many Pacrim countries). Brief comment will discuss the usefulness of accreditation and ethics codes plus other specific codes (eg JORC/VALMIN and their international analogues in Canada, South Africa, etc) in reducing risks.

Jan 1, 2004

The Savage River Mines concentrator and pipeline has operated for seven years. During this time some problems of general interest have been overcome, particularly in the area of autogenous grinding in large mills and in pump- ing solids over long distances. The plant flow sheet and equipment at Savage River and the control techniques are. described. Ore type has varied widely over the per- iod of plant operation. Techniques developed to minimise the effect of variations on through- put are discussed'. The main technique is the controlled rejection or addition of grinding Media.

Jan 1, 1975

Extensive infrastructure construction works were required for the development of the underground and open-cut coal mine at Ulan to a production capacity of 5 million tonnes of steaming coal per annum. The Ulan Mine development project was constructed in a two year period at a cost of $240 million. The infrastructure component included the construction of the mine site building works, civil works and 150km of railway, valued at $105 million. These works were successfully completed under a construction management agreement within two years. The separate elements of the project are described in detail in the paper.

Jan 1, 1983

By M Miettinen

That microorganisms, both living and dead, and products derived from the organisms, can function as flotation agents and flocculation agents is abundantly clear. They can modify the surfaces of minerals. They can function as flotation collectors and as flotation depressants and activators. In many cases they or their products can function as specific flocculation agents. Problems that must be solved before such microorganisms or products from the organisms can be used in commercial operations include culturing the organisms at a cheap cost and reduction in dosages required for various separations. These tasks are formidable. However, the concept of using such natural materials in place of various chemical reagents that may be toxic is very attractive. An attempt is made to show some of the promise of microorganisms in mineral bioprocessing and to consider the problems that must be overcome before commercial application of the technology is realised.

Jan 1, 2005

Cleaner Production stands for a proactive and preventive approach to industrial environmental management and aims for process- and/or product-integrated solutions that are both ecologically and economically efficient (æeco-efficiencyÆ). Pioneers in the field were large manufacturing and processing industries in the USA (since the late-1970s), but it took until the early-1990s before Cleaner Production was generally recognised as a valuable approach for large and medium sized enterprises. The application of Cleaner Production in mining and minerals, metals and energy production appears to lag behind other sectors, such as manufacturing and processing. This paper starts with a discussion of the Cleaner Production concept and provides examples of its application from a few selected Australian mining and minerals processing industries. This evidences that Cleaner Production can achieve significant reductions in environmental impact, in terms of reduced waste and emission generation and in terms of conservation of materials, energy and water, while simultaneously reducing operating costs. The paper then investigates a number of key issues pertaining to the implementation of Cleaner Production; ie organisation and management of Cleaner Production activities, effective tools for mastering the Cleaner Production concept as a way of life, and performance measurement.

Jan 1, 2002

By Pandey A. K, Srivastava A, Das A

Drilling and blasting constitute important activity in mining operations and account for around 20% of the total excavation cost. The utilization coefficient of energy for explosions of the fragmentation type is hardly 15 to 2035 and an enhancement in this is possible only through optimization of blast design. Designing a 'blast is a complex planning task, which for optimum results calls for matching the energy level of the explosive, rock properties and bench geometry. Optimum blast design needs a comprehensive study and an objective analysis of the intersecting elements. A cost optimised approach is often adopted with due consideration for all the cost sectors viz., drilling, blasting, loading, hauling dumping, and primary crushing, contributing to the overall miring cost. The present study deals with a performance prediction model which predicts the optimum burden for an explosive system in a given rock type to produce a certain desired fragment size. The model is framed on the inputs : shovel size, drill size, unit cost of drilling, bench dimensions, rock density, bond index, unit cost of explosive, maximum work potential. The model has been extended to compute the drilling and blasting costs for an assumed size of the bench to be blasted per round, so as to arrive at the overall cost optimization from a number of explosive systems. A comparative cost calculation with different explosive systems has been presented for a typical iron ore mine in India.

Jan 1, 1990

By B T. Park, S D. Fundingslan, K W. Wangerud

The EPA National Risk Management Research Laboratory (NRMRL) Mine Waste Technology Program (MWTP) and the EPA Region VIII Superfund office are jointly conducting a field-scale technology demonstration of a two-step in situ treatment of the acidic Anchor Hill Pit lake at the Gilt Edge Mine Superfund site near Deadwood, South Dakota, USA. The project goal is to develop cost and performance data for the in situ treatment for potential application in long-term water treatment/management activities at the Gilt Edge site, and for potential application at other similar sites. Lime neutralisation of the pit using a Neutra-Mill was accomplished in the spring of 2001, with a resultant lime utilisation efficiency of about 71 per cent, and a typical throughput of about 1 tonne per hour using coarse, pebble quicklime and 1.4 tonnes per hour using finer, ground lime. Redox-mediated biotransformation treatment of the pit has been ongoing since May 2001. As of January 2003, denitrification is complete in the near-surface waters and about 90 per cent complete in the deeper waters. Bacterial sulfate reduction is expected to begin in the near future. This paper describes project activities, results, and lessons-learned to-date as well as future monitoring plans.

Jan 1, 2003

Ranger Uranium Mines Pty. Ltd. operates an open pit mine and ore treatment plant in the Northern Territory designed to produce 3 000 tonne/yr of U308 in yellowcake from 3 500 tonne/day of mill feed. The construction of this project was completed in 1981, 12 years after the discovery of the orebody. Wright-Davy, a Joint Venture of Wright Engineers and Davy McKee Pacific, were the Project Managers and Designers of the $270 million ore treatment plant and associated infrastructure. The project was designed in Sydney in -an office integrated with the Client, staffed by 35 key personnel drawn from Wright Engineers and Davy McKee, supplemented by personnel hired for the project. The peak Wright-Davy workforce in Sydney of 200 contained 113 design staff. The design principle of using the best practicable proven technology resulted in a plant which easily produces its design output using ore types outside the design criteria. The structuring of the project systems and industrial relations policies contributed to construction being completed within time and under budget. The plant was built without any major industrial dispute occurring and no dispute arose due to the uranium issue.

Jan 1, 1983