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Oxidation or sulphidization of the surface of pyrrhotIte partIcles enhances atomic interdiffusion at elevated temperatures and provides a mechanism for interface growth between particles in contact. In a mass of pyrrhotite-rich ore or tailing, where oxidation heating is not controlled, bonding of particles by diffusional mass transport contributes significantly to the agglomeration of the mass.

Jan 1, 1976

Operation of the tankhouse at the Electro lytic Refining and Smelting Company's works has been improved, but further automation is re- quired to cut the labour intensive nature of the routine tasks. Anode quality, both chemical and physical, plays an important role in efficient refinery practice, and impurities such as lead, antimony and nickel have required careful monitoring for smooth operation. The gradual replacement of copper blanks by titanium has markedly improved the quality of starting sheets, but problems have been ex- perienced with surface preconditioning of the titanium blanks. Polishing with emery paper proved to be a successful technique.

Jan 1, 1976

An attempt was made to determine the lateral extent of analcite in the Newcastle Coal Measure sediments of the Sydney Basin. From an examination of the cores of eleven bores it was concluded that the mineral is concentrated in the western sector of the original Newcastle Basin and this presumably was the region of greatest sodium concentration and aridity. The distribution of the analcite is such that it appears to have little correlative value.

Jan 1, 1967

Until recently, the Australian mining industry received unquestioning encouragement from both State and Federal Governments. Now governments adopt a more questioning outlook about, for example, the proportion of local mine income accruing abroad, about the contrib- ution of the industry to public revenue, and about the industry's impact on the environment. This paper reports on attitudes at a recent industry-government-academic conference on planning and problems for the minerals sector in the next decade and beyond. It also examines a government policy review in Canada, which has undertaken some change in direction of mineral policies in the last few years.

Jan 1, 1977

By Champigny N, Grimley P. H

To a bank that granted his request for a loan, the late American humorist Robert Benchley responded, `I don't trust a bank that would lend money to such a poor risk'. This quotation is unlikely to be the norm among mining companies that secure project financing. However, a poor appreciation of one of the key risks of a mining project, the reserves, often results in disastrous financial consequences. This conclusion is the subject of the discussion and analyses presented in this paper.

Jan 1, 1994

By Conway KM

The traditional role of Australian Consultants in project development has been until recently restricted to the provision of discrete packages for survey and engineering services during the feasibility, design and construction phases of a project. Management of such projects was the province of the owner/developer or his agent. However, Australian Consultants are now being con- sidered for an expanded role on resources Projects.

Jan 1, 1983

Inadequate understanding and/or assessment of technical and economic risk associated with geological uncertainty are key reasons many mining projects do not achieve forecast profitability. In the last 20 years many new and existing mines have experienced geology related problems, including lower than planned development and production rates, geotechnical/stability issues, unplanned dilution, ore loss, reduced metallurgical performance, environmental management concerns and unbudgeted capital/operating costs. Greater emphasis on the evaluation and communication of uncertainty associated with geological interpretations for feasibility and operations management results in better decision-making. The outcome of better decision-making is more efficient mining yielding enhanced financial returns for the mining industry.

Jan 1, 2009

In December 1997, a series of new environmental legislation was enacted including:ò Environmental Planning andAssessmentAmendmentAct 1997; ò Contaminated Land ManagementAct 1997;ò Protection of the Environment (Operations) Act 1997; ò Native Vegetation Conservation Act 1997; andò Pollution Control (Load Based Licensing) Act 1997.These new Acts will have varying degrees of impact on the coal mining industry in New South Wales when they commence later this year.

Jan 1, 1998

By Fitchett K

Refractory application in the major iron and steelmaking units are discussed. Mechanis- ms of refractory consumption as revealed by pre- vious studies are reviewed and current practice is evaluated. Deficiencies in refractories now in use are noted and some lines of development are indicated. The iron and steelmaking units discussed are generally restricted to those subject to slagging, structural change or erosion at steel or iron making temperatures, and include the Blast Furnace, Hot Blast Stoves, Hot Metal Ladles, Basic Oxygen Furnaces, Continuous Cast- ing Units and Steel Teeming Ladles.

Jan 1, 1972

A vital ingredient in ensuring that metals exploration companies, working in the developing countries of the Pacific Rim, support the development of national geologists is making such a learning program cost-effective. There is a wide spectrum of learning needed in the development of these explorationists: the technical and conceptual skills to carry out exploration efficiently, the professional and managerial skills to apply the exploration in the work situation, the personal attributes required to manage their exploration effectively, and a company organisation that allows them to learn and use these skills and attributes.

Jan 1, 1995

By Morrison J

Considerable confusion is to be found in the methods of estimating mineral reserves. The solution appears to be more cooperation between industry and government to agree upon a classification system with guidelines to overcome the problem of the many variable factors affecting reserves. The classification system proposed by the United States Bureau of Mines and the United States Geological Survey (USBM/USGS) together with the guidelines similar to those suggested by the Australasian Institute of Mining and Metallurgy/Australian Mining Industry Council (AusIMM/AMIC) is recommended for reporting mineral reserves to government.

Jan 1, 1979

By M Lellis

During the last decades, maintenance has changed from an ordinary repair activity to a complex function that plays an essential role contributing for the companyÆs results. The increasing level of complexity of modern equipment motivates maintenance personnel to improve both techniques, and management systems, in order to face the new challenges. Managing properly those modern means of production requires knowledge of methods and planning systems, controlling and performing maintenance tasks, in such a way that two objectives are achieved at the same time: system efficiency and cost-effectiveness. This paper shows CVRDÆs experience on evolving and implementing a model to plan and manage maintenance activities in order to achieve a higher level of performance on its operations.

Jan 1, 2003

The three main types of iron ore deposits in Australia are bedded, massive and residual. Some character- istics of iron ore, important in its process behaviour, are related to its mineralogy which is a result of its geological history. World iron ore resources are extremely large but there are problems in quantifying re- serves, defined as that part of re- sources from which a useable commodity can be extracted economically. The relationship between the discovery and exploitation of iron ore resources and the process of industrialization is examined in historical and present day contexts.

Jan 1, 1976

Expert systems have been employed in a number of areas for a considerable number of years. However, the traditional long development times associated with these systems have restricted their application. With the advent of powerful Expert System Development Tools such as COMDALE/X and the use of efficient development techniques, the time required can be drastically reduced. This results in the availability and applicability of this technology to a wide range of applications. This paper discusses some of the 'rules' which indicate amenability (or otherwise) of a particular problem to an expert system solution. Various problem types are examined and these are illustrated with reference to examples of their use at various operating sites.

Jan 1, 1991

By Larsen E. R

We discuss the concept of optimal cut-off grade policies and their advantages in terms of maximisation of net present value of mining operations. There are indications, however, that such optimal policies are not widely used in the mining industry. In order to explore why this is the case we identify a number of stakeholders who may have diverging interests in the operating policies of a given mine. These various interests are mapped and a number of important relationships are explored in a large qualitative systems dyanmics model.

Jan 1, 1995

The reasons for using SFRS, including the way a SFRS performs in comparison to plain shotcrete as a support element in mining tunnels, are discussed. The mechanisms by which steel fibres reinforce shotcrete and the need for specifying performance criteria are highlighted. A description of current testing procedures, including an overview of æquantitativeÆ design recommendations provided from various international authorities, is provided. A summary of international recommendations on suitable æqualitativeÆ performance classifications is also reviewed, including a critique of their suitability. Finally recommendations on the practical considerations necessary to ensure good quality, in-place SFRS, are made, including a calculation method for determining minimum steel fibre dosages.

Jan 1, 1999

Peraluminous metamorphic rocks may form from a variety of protoliths by a range of processes. Stratiform bodies of such rocks are relatively common in the Precambrian, but less commonly, also occur in the Phanerozoic. The protoliths of such stratiform bodies may have been regionally deposited chamosite-rich sediments, with varying amounts of clastic component, or may have resulted from the in-situ depositional or diagenetic alteration of volcaniclastic sediments, ranging in composition from rhyolite to basaltic andesite.Stratiform peraluminous metasediments, especially those of low to medium metamorphic grade, and relatively iron rich, may be genetically associated with, or be the host rocks for, a variety of styles of mineralization, especially for the ores of An, Ag, Cu, Zn and Pb.

Jan 1, 1990

The difficulty of successfully imple menting a landscape policy is almost incom- prehensible. Landscape design is recognised as an essential component in the integration of engineering and architectural projects into the landscape, but the factors which prevent the achievement of a successful result are rarely recognised or assessed. In many cases these prohibiting factors are due to a lack of understanding of the effect of major planning decisions on the existing landscape, the importance of the landscape plan and the significance of appro- priate specified techniques to prevent un- necessary damage and to ensure retention of existing vegetation in a healthy condition. The role of the landscape architect in incorporating new land uses into the landscape provides the background against which factors which inhibit policy achievement can be con- sidered.

Jan 1, 1976

By Keren Z, Huanguo G, Jlchuan Q

In this paper, the authors introduce a new flotation technique, a double collection flotation precess, which succeeds in separating feldspar from quartz effectively in weak acidic medium (pH = 5-6). In the presence of sodium hexametaphosphase(HMP), sodium oleate selectively improves the floatability of feldspar in the first collection step. Dodecyl amine- hydrochloride is used as collector in the second collection step to separate feldspar from quartz. The flotation tests with pure minerals as well as artificial mixture give out satisfactory results. The mechanism of reagent effect was investigated briefly, which is helpful for understanding the Process.

Jan 1, 1993

By Di Pasquale S, Osler GD

Mount Isa Mines Limited recently commiss ioned an 800 tph Heavy Medium Preconcentration Plant for lead/zinc/silver ores. The decision to build this plant was made in late 1979 based largely on investigations conducted in the Company's pilot plant on a variety of ore types including Hilton ores, between 1972 and 1978. The paper reviews the historical develop- ment of the pilot plant heavy medium circuit through this period and illustrates the extent to which this work impacted on the final design criteria. This review also includes a description of plant operation, manning levels, process equipment and metallurgical performance Achieved.

Jan 1, 1978