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In the context of sustainable development, the Minerals Council of Australia (2010) states that 'investments in minerals projects should be financially profitable, technically appropriate, environmentally sound and socially responsible'. In other words, the business of mining can only be sustained if these criteria are met.   Science and technology plays a major role in all four of these criteria. This paper will present the technology and innovation emerging from the Minerals Down Under National Research Flagship which brings together CSIRO and more than ten of Australia's leading universities to work with industry to drive efficiency, productivity and environmental performance. This work is required if the Australian minerals sector is to thrive and continue to deliver national benefit in the face of increased global competition, declining ore grades, depleting ore deposits, increasingly constrained national resources (land, energy, water and people) and changing societal expectations.   Science and technology to reduce emissions and water use, discover greenfields resources, enable deeper mining operations and transform mineral processing are described. Technology is presented as an enabler of sustainability: a means to this end but not as an end in its own right.

Jun 1, 2010

By Bohrn W, Milionis K, Tessmer G, Reidetschlager J

The share of electric arc furnace based steel production is increasing - New technologies for the production of virgin raw materials for EAF production are under development and on the market - VAI has a strong position in the field of scrap substitution technologies with their COREX«-, COREX«-DR and FINMET«-technology. In late-1998 the steel plant SALDANHA was started up successfully. This integrated compact mill is using the COREX«-technology as hot metal and a combined DR-plant as DRI production unit. Also in 1999 the BHB FINMET« plant Port Headland went on Stream.

Jan 1, 1999

Reconnaissance geochemical exploration in the vicinity of low angle detachment faults which bound the core of the Paparoa metamorphic core complex yielded Au up to 14 ppm, with 35% of greywacke, granitoid and quartz vein samples in the northern range exceeding the 0.01 ppm detection limit. Au is associated with Ag, As, Sb and Cu anomalies consistent with epithermal-type mineralisation. The Ag and Cu anomalies also distinguish this mineralisation from older, mesothermal Au deposits widespread in the Ordovician 'slate belt' greywackes, which comprise much of the upper plate of the core complex. Baryte, molybdenite, fluorite and stratiform U mineralisation in the northernPaparoa Range may also be related to hydrothermal activity along the detachment fault zones.

Jan 1, 1995

By J L. Mauk

The Sovereign, Jubilee, Scotia and Jasper Creek prospects occur in an area of ~3.0 km by 2.5 km (~7.5 km2) in the Hauraki goldfield. The prospects are hosted by andesitic to dacitic flows, autoclastic breccias and localised pyroclastic and air fall deposits. Jubilee and Sovereign prospects lie along the northern and southern parts of the Waitekauri Fault, respectively, whereas Scotia is located ~1 km to the E, and Jasper Creek a further ~1.2 km to the ENE. Wall rocks are typically intensely altered, although the degree of alteration becomes more variable east of Scotia and at Jasper Creek. Alteration minerals include quartz, adularia, albite, chlorite, pyrite, illite, interstratified illite-smectite, smectite and calcite. Several of these minerals have distributions that show distinct zonation with adularia most abundant at Sovereign and Jasper Creek, but restricted to shallow levels at Scotia. Illite occurs throughout Sovereign and Jubilee plus the western margin of Scotia where it grades into interstratified illite-smectite; smectite predominates at Jasper Creek. Veins are uncommon and typically narrow, but show distinct zonations. Quartz veins are more abundant at Sovereign and Jubilee, whereas calcite veins are more abundant at Scotia and Jasper Creek. Laumontite veins occur at Scotia, and rare clinoptilolite, mordenite and stilbite veinlets with calcite occur at Jasper Creek. Fluid inclusion in quartz and calcite homogenised between 141¦ to 272¦C and trapped a dilute solution with an apparent salinity of less than 2.6 weight percent NaCl equivalent. Homogenisation temperatures are hottest at Sovereign (average 241¦C) and Jubilee (average 239¦C), cooler at Scotia (average 204¦C) and coolest at Jasper Creek (average 162¦C). Calculated paleowater table elevations suggest the water table was 680 m to 750 m above sea level at Sovereign and Jubilee, 450 m at Scotia and 225 m at Jasper Creek. The current data suggest three scenarios that can explain why Sovereign and Jubilee are deep and hot, whereas Jasper Creek is cool, shallow and marginal; 1.   some or all of the prospects may represent separate overlapping hydrothermal system, 2.   a high-relief hydrothermal system on the side of volcano with an inclined water table and outflow towards Jasper Creek, and 3.   a low-relief hydrothermal system that has been either tilted or block faulted with greatest uplift and erosion to the west.

Jan 1, 2005

Many sampling standards arrive at a value for the prescribed sample mass by assuming a specific relation between the sample mass and the relative standard deviation of the fundamental error and assigning a value to the tolerated coefficient of variation. In order to obtain an equation that provides a relation between the minimum sample mass and the particle properties, many different models for the drawing of a sample have been developed. Here, a model for the drawing of a sample is proposed which can be considered to be a generalisation of the model used in GyÆs sampling theory. Using simulations, it is illustrated that the generalised model can lead to a better correspondence with actual sampling processes.

Jan 1, 2005

Triboelectric Charge and Separation Characteristics of Industrial Minerals The basic principles of triboelectric charge and separation of minerals and the factors affecting the entity of the charges developed on mineral surfaces are discussed and the surface pretreatment methods by which the electrophysical properties and thereby triboelectric charging and separation of minerals can be artificially altered/modified are reviewed. Furthermore, the triboelectricfication theory of materials is envisaged from the chemical concept of acid-base donor-acceptor and an attempt is made to correlate the physical concept of triboelectrification with the donor-acceptor properties. The triboelectric charge characteristics of the quartz, calcite and wollastonite mineral samples for different size classes were defined using different tribocharging medium. Based on the triboelectric charges acquired by mineral samples their energetic work function values are estimated. In addition, the main electrophysical properties, ie dielectric constant and electrical conductivity, of different size fractions of the mineral samples are measured and their donor-acceptor chemical properties were defined. A series of triboelectric separation tests were conducted to explore the possibilities for separation these mineral from each others. The results from the triboelectric charge and separation of the single mineral systems showed promising prospect in separating quartz, calcite, and wollastonite from each others. Finally, attempts were made to explore the possibilities to implement triboelectric charge and separation process to real ores. Promising results achieved when separation of calcite from silicate impurity was sought from a carbonate ore. A very high purity (99 per cent) calcite product was obtained at a recovery of 80 per cent. Interesting results were also achieved to concentrate wollastonite from a complex silicate ore containing quartz, different feldspars, wollastonite and other Mg-Fe silicates. In this case conditioning of the ore with salicylic acid at defined temperature and relative humidity was found to be essential to concentrate wollastonite. The outcomes indicate despite the fact that triboelectric charge and separation process has not been completely perceived, it pronounced to be an environmentally friendly and economically viable technique for minerals and wastes beneficiation. Being a dry beneficiation technique the process has special appeal, which must be explored further in particular for treating industrial minerals.

Sep 13, 2010

Measurement of densities, susceptibilities, permanent magnetization, and calculation of demagnetization factors has allowed computer modelling of gravity and magnetic data over the Middleback Range iron formations of South Australia. As well as providing structural information, the study emphasizes the effects of weathering on the interpretation of magnetic data.

Jan 1, 1975

Investigation on Multicomponent Semi-Autogenous Grinding

Sep 13, 2010

By P Hatherly, H Gurgenci

With the depletion of the mineral reserves that can be mined by surface mining, demand for highly productive and safe underground mines will increase. Underground drill and blast techniques continue to be refined but true æmass productionÆ is difficult to achieve. As is evidenced by the longwall mining of coal, alternative mining methods based on mechanised mining can meet the expectations but the issues of how to effectively cut strong rocks, how to define the orebody and how the mechanised miners can be automated and maintained all need to be addressed. CMTE is working in all of these areas. We believe that the oscillating disc cutter may provide the long sought-after breakthrough in mechanised rock cutting. Disc cutters are one of the most robust designs of cutting tool and the cutters attack the rock in a manner which effects direct tensile breakage. The internal cutter drive and the inertial damping mean that the already low cutter forces are not all transmitted back to the machine, making it possible to design lightweight, flexible mining systems. For orebody delineation drill monitoring, drillhole logging and geophysical imaging are key procedures being developed at CMTE. To automate mining machines, work is progressing well in the development of systems for autonomous vehicle navigation and mining robotics. A strategic contribution to maintenance issues is being made through the development of procedures for automatic analysis of used oils, monitoring the strength of mechanical structures, and operating point optimisation.

Jan 1, 1998

Coking coals are very much in demand on a world wide basis, particularly the higher rank coking coals, which form an important part of many coking blends and which represent the smallest portion of the world'scoking coal reserves. Conventional coke oven plants, using these coals, will predominate at least until the next century.Blending schemes for conventional coking require definition of the basic properties of coals so that the factors influencing the carbonization behaviour may be assessed. Several concepts, which are relatively simple, ate available to help promote a better understanding of the bask factors controlling -coke strength and are also useful in suggesting possible lines to follow in the blending of coals for coking.The interpretation of carbonization behaviour and coke structure in terms of petrographically defined coal rank and type provide a basis for planning and exploitation of coal Teserves. The optimum parameters for coking are suggested as follows.1. Type- Vitrinite content (% m.m.f. by volume) 55 ± 5%2. Rank- Mean maximum reflectance of vitrinite 1.30 ± O.10% Carbon content of vitrinite (% d.m.m.f.) 87·5 ± 1·0%The value of a coal should be assessed in relation to all its possible uses in blends. This is a more realistic and productive approach, as compared with considering coals only in relation to the results of blending with"good" coking coals. Blending schemes have been outlined to assist in the assessment of the blend potential of coals of all ranks and types.Reserves of higher rank coking coals in N.S.W. are very limited and should be conserved by blending with the low rank coking coals, of which there are large reserves.Examination of blending theories in relation to N.S.W. coals suggest that blends in the broad categories of minimal downgrading of the higher rank N.S.W. cok...

Jan 1, 1972

By KEITH BARRONI

In the proposed criterion for coal a distinction is made between brittle and "psuedo-ductile" failure. This criterion is the basis for the development of new equations for coal pillar strength, including a transition from brittle fracture to pseudo-ductile yielding. In addition the equations obtained allow the critical minimum pillar dimensions to be calculated to avoid "catastrophic" and "ultimate failure".The validity of these formulae can be tested by comparing their results with pillar case histories derived from the literature.

Jan 1, 1988

By Holla L, Tyminski A

Stowing has been successfully used in many countries as a means of controlling surface subsidence, minimi ing incidences of spontaneous combustion, maintaining gate road stability and maximising coal recovery.Australian experience in stowing is limited but in the future increased extraction of thicker and/or multiple seams by longwall operations and resolution of conflict of alternative land u'ses may necessitate the use of stowing in coal mining. At present there is little incentive for mining companies to introduce and operate a stowing system because costs have to be borne by the individual companies and benefits spill over to society and the State. Cost sharing by the industry and State incentives may overcome the problem of cost disincentive.

Jan 1, 1987

S. R. Carter (Mount Isa Mines Ltd., Mt. Isa): I found many ideas to interest me in Haddon King's paper "Notes on Ore Occurrences in Highly Metamorphosed Precambrian Rocks" (Stillwell Anniversary Volume).At Mount Isa I have not been happy about some of the longstanding appreciations of the geological evidence as fresh data accumulated, and as more and more knowledge has been building up outside Mount Isa in recent years of sedimentary deposition of sulphides.Accordingly, I organized a small section of the Geological Department at Mount Isa at the beginning of 1958 under Senior Geologist, W. J. Murray to reappraise our geological record and investigate old interpretations and new ones that arise. The work is expected to take several years to complete, but it is hoped that sufficient will be done before then to permit the most plausible story on the ore genesis to be chosen. In the meantime, W. J. Murray has proposed, in a Company Report, that the.epigenetic features of the silver,lead-zinc deposits, which are essentially conformable with the shales, could have resulted from remobilized syngenetic deposits.Haddon King, on p. 159; has listed six assumptions that are required by a magmatic-hydrothermal theory of, origin for conformable deposits. It is interesting to consider the Mount Isa silver-lead-zinc deposits in terms of these requirements.My comments are listed in the same order as Haddon King's assumptions:(a) "The source of the constituents is magmatic and they have become available in successive waves of zinc-rich, lead rich, manganese rich, silver rich, etc, instalments in accord...

Jan 1, 1959

By Andrew A. A, Hamilton P. J

Constraints on pore water evolution in the aquifers of a sedimentary basin may be realised through stable isotope analyses of present day waters, and their comparison with water compositions calculated to have been in isotope equilibrium with the products of diagenesis during burial. Integrated with detailed petrographic observations, and thermal, structural and stratigraphic analyses, fluid migration patterns at various stages in a basin's history can be identified. This has important implications for modelling basin hydrology, hydrocarbon distribution, and reservoir quality in the Latrobe Group, Gippsland Basin, and oil-prone successions Elsewhere.

Jan 1, 1992

When a thin film of volatile matter is deposited under vacuum on a polished coal surface, and the coated surface is examined microscopically in plane-polarized reflected light, colour changes are observed which are characteristic of the various macerals present. The colour changes appear to be mainly due to interference between light reflected at the upper surface of the film and at the film!coal interface. A variety of source materials for the volatile matter required have been tested, including powdered bituminous coal, coal tars, boron oxide, and certain resins. Bituminous coal gave the best results.

Jan 1, 1970

The physical setting and background to mining operations on Misima Island and the overall plant lay-out are outlined. Developments and changes made to each section of the plant are described as they were encountered during commissioning and initial operation.

Jan 1, 1991

By Hillis R

As part of BHP Iron Ore's policy and goal of achieving a high standard of environmental management within its operations, a protocol for mine closure has evolved. The need to demonstrate sound environmental management with respect to site decommissioning meant that a comprehensive, environmentally sensitive closure protocol was required. Within this framework, a four-phase protocol was developed, the first phase was the determination of objectives in relation to site rehabilitation and end land use. The second phase was the determination of the process required to achieve these objectives. The third phase was the application of this process in a site specific manner. The fourth and final phase was monitoring of the site with regard to the achievement of determined objectives. The protocol was originally developed to direct the closure and decommissioning of the Goldsworthy site in 1992. This being the first total site decommissioning for BHP Iron Ore. Since that time the protocol has been successfully utilised for the closure of the Yampi (Koolan Island) operations (in 1993/94) and the Shay Gap/Nimingarra Operations (in 1994/95).

Jan 1, 1996

By Milner A, Brockway D, Hodges S

The combustion of brown coals in Latrobe Valley power stations produces approximately 500 000 tonnes of solid wastes each year. This material, which includes precipitator ash, char and furnace ash, is hydraulically sluiced to large ashing ponds and the supernatant solution is ultimately discharged to the sea. There are significant operational and capital costs associated with the current ashing system. The ash produced from the Latrobe Valley coals is unique and has a wide variety of potential applications including soil conditioning, concrete and cement extenders, fillers in non-metallic materials, components of building products. In addition, with the application of appropriate technology, it is possible to extract char, sodium sulphate, calcium carbonate and magnesium metal (as the chloride) in substantial quantities from the ash. Research has been carried out to explore the prospects of these various options for ash utilisation. The research has focused on detailed characterisation of the ash material and the potential extraction efficiency for various species under various conditions. From this work a conceptual process has been developed and subsequent studies have been directed towards understanding variables and optimising operating regimes for product extraction. Currently, the work is concentrating on the separation of char, the development of high-grade carbon products and the extraction of sodium sulphate.

Jan 1, 1992

The Effect of Using Different Comminution Procedures on the Flotation of Platinum Group Minerals The use of High Pressure Grinding Rollers (HPGR) has been widely reported to have major benefits in the treatment of minerals such as iron ore and diamonds. To date there have been few investigations into its use in the treatment of ores containing Platinum Group Minerals (PGMs). HPGRs are known to reduce energy consumption and wear costs and improve the throughput in the circuit. In the present investigation the effect of the comparative use of HPGR and conventional crushing in combination with either dry or wet rod milling on the flotation of PGMs was studied using batch flotation. Previous studies of a base metal sulfide ores had shown that either HPGR or conventional crushing followed by dry milling produced the highest grades and recoveries. However in the present study it was observed that a similar treatment produced the worst results and the highest grades and recoveries were obtained for the case of conventional crushing in combination with wet milling. The HPGR showed no advantages in terms of flotation performance and dry milling produced particularly poor flotation results. The results were investigated further using various surface characterisation techniques in order to determine the reason for the decrease in grades and recoveries of platinum when using dry milling and HPGR as opposed to the case for base metal sulfides. The feed and product samples were analysed using ToF-SIMS, XPS and MLA. The paper will propose reasons to explain the different flotation behaviour of the two ore types following the various comminution processes focusing on the surface characteristics of the ores, the particle size distribution and the pulp chemistry.

Sep 13, 2010

By R L. Brathwaite

The orogenic gold deposits wall poster is one in a series of posters on different mineral deposit types being produced by GNS Science to raise awareness of the characteristics of New Zealand mineral deposits and their prospectivity. Orogenic gold deposits are typically quartz vein deposits formed in fault and shear systems at crustal levels within and above the brittle ductile transition zone, at depths of 3 12 km and temperatures from 200¦ to 400¦C. In New Zealand, orogenic gold deposits are found in regionally metamorphosed sedimentary rocks of Paleozoic and Mesozoic age. The deposits in Paleozoic rocks include those at Golden Blocks in Northwest Nelson, Lyell and Reefton on the West Coast, and Preservation Inlet in Fiordland. Quartz veins are developed along shear zones that dip steeply and generally strike parallel to the axes of folding in the greywacke and argillite/slate host rocks, although most are discordant to bedding. The lodes are typically less than 1 m wide and extend an average 200 m horizontally and vertically, but the Birthday Reef at Blackwater, Reefton, the largest quartz vein deposit in Paleozoic rocks, averages 60 cm in width and was mined over a strike length of 1070 m, and to a depth of 830 m. Disseminated gold occurs adjacent to the quartz lodes at Globe-Progress and some other Reefton deposits. The deposits in Mesozoic rocks are hosted in schist of Otago and Marlborough, and schist and greywacke of the Southern Alps. The lodes are typically lensoidal, less than 1 m wide and localised along single or multiple parallel shear zones that generally dip steeply, and are discordant to the schist foliation and bedding. A notable exception is Macraes, where the lodes are developed in the semi-concordant, low angle Hyde Macraes Shear Zone that has a strike length greater than 25 km.

Jan 1, 2005