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The commonly used stainless steels, their properties and uses are briefly discussed.Two specific topics are then explored in more detai's to highlight development areas, the potential of which has been largely unexploited in mining milling, refining and smelting operations. The high strength to weight ratios achievable in austenitic stainless steels has been widely used in the transport industry to design high integrity light weight vehicles,especially railway carriages. This use has rarely been extended into other structural areas where highly aggressive environments could make stainless steel a cost effective material compared to protected carbon steels. The recently developed weldable ferritic steels are described and their potential in materials handling discussed. Particular attention is paid to 3CR12, a nominal 12% Chromium, titanium stabilised steel finding wide acceptance in the mining industry.

Jan 1, 1985

Process control computers are finding ever increasing applications within the chemi-cal and mineral processing industries.To purchase a system which fulfils both the immediate and future needs of operating, technical and management groups, requires an appreciation of the capabilities of the system software and the constraints which apply to user development of application software. Early decisions are then required as to who will develop and maintain the software. Rules and conventions must be determined and adhered to if the end result is to be an orderly, well structured and properly documented system. Software development and maintenance represents a substantial, and often hidden, cost. Getting it right the first time will avoid either a major re-work, or having to live with a system which is extremely diffi-cult (at the worst, impossible) to trouble-shoot or modify.

Jan 1, 1985

Australia is the dominant iron ore supplier to the Asian market, a position that began to emerge with the development of the Pilbara in the 1960s. Iron ore is now one of AustraliaÆs main commodity exports and is likely to remain so well into the future. The annual price negotiations are the focus of widespread comment and speculation by financial analysts, journalists and mining professionals. Much is written on the subject, but how much is understood? What is the process all about and what can mine managers learn from understanding the pricing mechanism? Every one of the major regional iron ore markets has its own characteristics. The focus here is Australian supply specifically to Asia, far and away the biggest and fastest-growing of these regional markets. The core of the paper reviews and explains the key elements and procedures that contribute to pricing iron ore in Asia, a market that has long been dominated by the Japanese steel mills (JSMs) and that is now feeling the full force generated by the rapid industrialisation of China. First, however, it is important to understand how this market has evolved over the past 40 years, and the key relationships that have shaped and continue to shape the iron ore price. A description of the essential technical and commercial factors follows. Each area is explained in some detail to provide an overall demonstration of the linkages and the importance of understanding the various influences on the pricing process.

Jan 1, 2006

Projections of metal requirements for Japan and the United States indicate growing competit- ion for Australia's mineral output and a critical need for continuing discovery of new reserves. These projections may be modified by economic, social and political controls - the most import- ant factor probably being a shortage and the high cost of risk and development capital. Changing ownership patterns toward joint ventures and increased state participation are anticipated. New developments in global tectonics and metallogeny delineate favourable zones for ex- ploration and permit establishment of priority search areas even in regions of poorly known geology. Declining ore grades and special character- istics to meet technological requirements may modify identification and evaluation criteria. A broad approach considering all environments of concentration within the geochemical cycle is re- quired within any metallogenic province. The exploration geologist must be able to integrate geological theory, mining technology and financial analysis to establish well defined exploration objectives, in terms of economic and geologic models, in concept-oriented programmes.

Jan 1, 1973

By J Wiklund

The impact of non-ferrous smelters on their local surroundings is well monitored and guarded by various actors: the owners looking for profitability, the villagers looking for employment, the consumers asking for ever cheaper products and services, the government collecting taxes and all cherishing the environmental impact. Recent challenges facing the industry are various new doomsday projections: that we will be running out of base metals, that the ground we dwell on will be contaminated by the use of products. Smelters, such as BolidenÆs R÷nnskSr Smelter have a long history of increasing non-ferrous resources by recycling. It is shown that extraction and recycling of metals together with energy recovery can be integrated in a modern, profitable and clean smelter. Examples of efforts to further improve the business will be discussed such as flowsheet rationalisation, environmental investments, new feed from recycling and energy utilisation.

Jan 1, 2000

In the time since the first trials in the mid-1980s, the Rare-Earth Magnetic Separators (REMS) are presently (year 2001) found in many heavy mineral sands plants around the world. Both the roll and the drum type are used from ilmenite concentration to cleaning high-purity zircon products. Chromium-bearing materials are removed from ilmenite more selectively than with electromagnetic separators. Greater flexibility and higher grades in ilmenite circuits are achieved. Cleaner rutile and zircon products, even with respect to levels of radioactive materials, are the result of superior magnetic force optimisation. Tailings from roaster plants can be reprocessed effectively, which is encouraging some operators to look at replacing old equipment in order to process roasted material plant feed or implement use of the new generation drum separators in new plants. Wet separation of ilmenite by using powerful wet REMS drum separators is now a possibility. This may be an alternative to at least a portion of the Wet High-Intensity Magnetic Separators (WHIMS) process for ilmenite preconcentration. A dry plant process flowsheet can often be modified by displacing a portion of high-tension separators with new high-temperature tolerant REMS.

Jan 1, 2001

An efficient energy management programme can often significantly reduce a company's energy costs. The programme consists of a series of steps, namely a statement of support from senior management, assigning the management team, the energy audit, defining the goals and comwnicating with and training employees. The energy audit provides the information base from which the company can start to control and improve upon energy Usage.

Jan 1, 1983

Coal exploration and mine planning now use all the modem techniques to indicate geological hazards to a new or developing coal mine. Drilling, seismic and other sophisticated geophysical methods aim to increase the reliability of prediction of features which will inhibit mine development. But do they?. During the past 40 years, geological investigations for coal mines in New South Wales have ranged from the general observations of Eric Rudd, in the Southern Coalfield in the late 1940s to the very detailed examinations of roof strata by John Shepherd and others in the 1980s. Then, the large scale regional relationships between sedimentary and structural features often were ignored as the minute examination of seam roof strata became fashionable.

Jan 1, 1991

By R C. Owen, M A. Ward

The paper describes the application of New Zealand's environmental impact assessment procedures to a proposed gold and silver mine in the North Island of New Zealand. The project is described and a summary is provided of the statutory permits or consents that are required prior to operation of the project. Emphasis is given to the requirement for environmental impact assessment and the preparation of a formal environmental impact report. The company's approach to impact assessment is described, with examples of how this assessment and the identification of management alternatives influenced the engineering design of the project. This paper was prepared as a contribution to a working session of the International Association of Impact Assessment VII Annual Conference, July 1988.

Jan 1, 1988

By Rao SR, Finch JA

Sphalerite flotation without Cu activation in the presence of iron ions has been reported and studied as a function of pH, dissolved oxygen content and pulp potential with both single mineral and ore samples (Leroux, Rao and Finch, 1987; Xu et al, 1992; Zhang, Rao and Finch, 1992). The flotation was attributed to ferric hydroxy xanthate. As a prelude to surface analysis to try to identify the species responsible, bulk precipitates formed from iron salt and xanthate solutions under different conditions were obtained and analysed. Analysis techniques included ultraviolet spectroscopy,infrared spectroscopy, X-ray diffraction and Mossbauer spectroscopy. It is tentatively concluded that the bulk precipitates contain three ferric components, two hydroxy xanthates (Fe(OH)2X and Fe(OH)X2) and iron oxide (FeO.).

Jan 1, 1993

By Luck D

Current methods of mucking out small development tunnels are a major limitation to improved efficiency and high rates of advance. This is particularly true in the deep metalliferous mines of South Africa, where the harsh environment, remoteness of operations and the hard abrasive rock conditions mitigate against the use of the tunnel borer type of equipment. The Loader Distributor Train was designed to overcome the special problems of hard rock tunnelling. It combines advanced innovative technology with proven simple methods of operation and maintenance. The system aims at taking advantage of new, efficient and cost effective power sources in South African mines based on replacing compressed air with electro hydraulics and the new concept of hydropower. It also introduces electronics and computer technology, for both automatic control and fault finding, into the production environment. The system is designed to permit sophisticated equipment to be operated and maintained by a semi skilled labour force. Although still undergoing trials it is believed that the Loader Distributor Train will prove highly effective, and that the new concepts offer considerable potential in areas other than flat tunnels, in particular the cleaning of inclined shafts.

Jan 1, 1986

By Alder KF

Nuclear power stations to be installed in Australia will be fuelled from Australian resources of raw materials. This will require the establishment of new manufacturing industries and the eventual expansion of established activities, especially in uranium mining and the preparation of precision metal products. This paper presents some predictions of the possible growth of nuclear power installations in Australia. These might amount to 4000 MWE by 1985 and 11,500 MWE by 1990 and towards the end of the century, about 50% of new generating plant might be nuclear. Predictions are given of the demands for materials (uranium and zirconium) and fuel manufacturing services for four reactor systems which might be considered in the programme. - The availability of raw materials and technical capability place Australia in a particularly good position to undertake the manufacture of nuclear fuel'; in addition to satisfying the domestic demand we should actively seek export markets for these products.

Jan 1, 1970

The nature of exploration in Australia is reviewed from its inception to the present time. It is seen as consisting of three phases: the first, prospecting; the second and third, mainly company-based activity. The first yielded the discoveries on which the mining industry was originally built. The great recent growth of the industry has been due mainly to the discoveries of the third. The technical, organisational, legis- lative and other aspects are reviewed. The overall result has been a very great increase in the known mineral resources and, viewed collectively, exploration is seen as providing the principal means of assessing, evaluating and building up the nation's mineral resources.

Jan 1, 1973

By Bebb G

This paper describes the use of SURPAC, a survey/mine planning software package as used at Central Norseman Gold. It details the basic operating principles of the package, the applications in which it is employed, and its time and cost benefits and efficiencies as they apply to the above operations, both surface and underground.

Jan 1, 1985

Conventionally, a combined system consist- ing of a dry or wet pulverizer and kneading mac- hine is applied to the pretreatment of fine mat- erials for agglomeration, especially for pellet- izing. However, treatment cannot be expected to be satisfactory owing to the complexities of the process. A new process was developed to over- come the defects inherent in the conventional process. This new process treats certain fine materials having a moisture content somewhat lower than that suitable for pelletizing in a ball or rod mill. The mill is of special de- sign in which grinding and strong kneading are performed to give an extremely homogeneous ball- ing material with appropriate size distribution and pelletizing characteristics. The most serious problem in this process is the choking of sticky materials in the mill. A specially designed rubber lining was installed in the mill to overcome this trouble. This paper presents actual results from our iron ore pelletizing plant relating to the pelletization of other fine materials.

Jan 1, 1974

Victorian brown coals occur in massive deposits, the quality of which is determined in the first instance by means of samples taken from exploratory bores. As a number of important utilisation characteristics are connected, not with the relatively homogeneous organic mass of the coal, but with minor components such as the ash content and particular constituents of the ash, it is necessary to know how bore samples relate to coal finally used in the process concerned. Tests are described in which the statistical parameters associated with bore sampling, operational sampling and sample reduction and laboratory procedures including a range of coal analytical methods were determined. These indicated properties where analytical errors were relatively high and where sample reduction procedures contributed substantially to imprecision in results. They also showed the effects of the non-homogeneity of brown coals with higher than normal ash contents. A further experiment explored the relationship between samples taken at various stages in the course of test boring, digging, and burning a defined 'block' of coal, and demonstrated an apparent increase in the proportions of adventitious mineral constituents as the 'intensity' of sampling Increased.

Jan 1, 1976

The Olympic Dam mineral discovery by Western Mining Corporation (WMC) in South Australia has been shown to contain one of the world's largest known deposits of copper and uranium; gold and silver are also present. Development of the deposit jointly by WMC and the BP Group is awaiting commitment, with planning based on initial production of gold in 1987 and copper and uranium in 1988.

Jan 1, 1985

By Williams DJ

Preliminary calculations suggest that spoil piles in the Bowen Basin will undergo approximately 4 m settlement as the ground water table recovers after mining is abandoned. Approximately 1 m of differential settlement is possible. Superimposed on this will be a long term creep settlement of 1-3 m/log cycle of time. Depending on the nature of the spoil material, partially submerged spoil piles could be sufficiently stable although to ensure stability during long term creep it may be necessary to flatten the final spoil pile face to approximately 25¦.

Jan 1, 1987

Because of the mineralogical complexity of nickeliferous laterites, most commercial and laboratory extractive processes require the ore to be blended to a feed of "constant" chemical composition. Even using the "constant" feed there are significant variations in processing behaviour within and between different feed lots. Chemical and mineralogical analyses of lumps of ore taken from the Yabulu stockpile of Queensland Nickel have highlighted the complex- ity of the ore making up the blended feed material. Each sample has been subjected to acid leaching and reduction/ammonia leaching tests and the results correlated with the mineralogical location of the nickel. The consequences of the variability in ease of leaching of the nickel are indicated.

Jan 1, 1978

Authorisation No.66 (to Prospect) was allocated to R.W. Miller & Co. Pty. Ltd. on 1st November, 1976. Exploration has brought coal reserves to measured status in the Jerry's Plains sub-group which are about 550m. thick. The immediately lower Vane Sub-group, about 200m. thick, includes about 20 seams. The total measured and indicated reserves of the two sub-groups based on the criteria adopted by the company amount to 1362 million tonnes in situ. This very large resource is subject to very many mining constraints both physical and economic which limit the saleable reserves under present conditions to about 120 million tonnes. The results of the calculation of reserves after exploration is complete in a deep multiple seam situation is dependent upon the criteria used to include or exclude seams in the reserves. These criteria are state- ments of the miner's expectations of the market, mining and coal preparation technology, local and national politics and the law as it may be applied in the future.

Jan 1, 1979