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By P T. Hick, T J. Cudahy, M S. Caccetta

Dust derived from mining and handling of ore has been identified as a major concern for the mining industry in Australia and may be critical to the future viability of some resource industries (CSIRO, 1999). Operational techniques to derive accurate measurements of anthropogenic dust on vegetation and infrastructure are necessary for the long-term management and monitoring of the environment surrounding mining operations. Airborne hyperspectral VNIR-SWIR systems can potentially provide these monitoring data. This paper outlines a method developed for deriving quantitative measurements of dust quantity on mangroves using remotely-sensed airborne hyperspectral data. The results show that it is possible to detect and quantitatively map iron oxide dust distribution using properly calibrated airborne visible to short wave infrared (VNIR-SWIR) data.

Jan 1, 2002

By Quast K. B

Laboratory batch rod and ball milling tests were conducted on samples of Heavy Medium Separator (HMS) sinks from Renison Tin Limited. The product size distributions for this heterogeneous material were very different to similarly sized homogenous material previously reported by the authors. The effects of pulp density on product size distributions were only evident at pulp densities greater than 80 per cent solids. At high solids density, the major weight distribution product peak fell and broadened indicating less efficient breakage, particularly for rod milling. Tin distribution in the ground products was also affected by pUlp density, and there was always less cumulative per cent tin than cumulative per cent weight, ie there was no tendency for cassiterite to slime down to 10/lm.

Jan 1, 1995

By Vutukuri VS, Budavari S

During recent years many investigators have suggested large spacing to burden ratios to improve the fragmentation obtained in blasting. In spite of these suggestions, most operators still use a conventional ratio of 1 to 2. From single hole longitudinal charge tests in laboratory, it is shown that burden controls the fragmentation. The burden for obtaining uniform fragmentation is smaller than the burden to obtain maximum breakage. Tests on two or three holes show that a larger spacing to burden ratio can be used for smaller burdens, but it is not possible for the larger burdens chosen to obtain maximum breakage. By using finite element analysis evidence is presented to show the effect of spacing and burden relationship on blasting results.

Jan 1, 1975

Metsim is proving to be a powerful tool when designing a heap leach operation. The most useful outputs arc determining the fluctuations in pregnant solution recovery rate, make-up water rate, gold recovery rate. and pond levels. Detailed data are needed for input: a pad loading schedule, a mining rate schedule for each ore type, column leach test data for each ore type, column tests on water dynamics (ie hourly flow-out versus-in during saturation and drain-down), monthly rainfall and evaporation data, and proposed pond dimensions. These data allow 'what if' studies on application rates, leach rates, loading rates and other variables of interest. Examples will he given of modelling both a rectangular pad and a valley fill operation.

Jan 1, 1994

A laminar-flow furnace was used to study the combustion of four flotation concentrates (chalcopyrite, pyrite, galena, and sphalerite) in air at temperatures up to 1400¦C. A special- Iv developed two-colour pyrometer was used to measure the temperature of individual chalco- pvrite and pyrite particles as they underwent combustion. Chalcopyrite and pyrite ignited with very high rates of reaction at air tempera- tures above 480 and 600¦C respectively, forming molten products. Galena and sphalerite required temperatures in excess of 700 and 1200¦ respect- ively to attain equivalent rates of reaction. The high rates of reaction for galena and spha- lerite were caused by vaporization. Temperature measurements for chalcopyrite and pyrite are reported here, together with vaporization measurements for chalcopyrite, galena, and Sphalerito

Jan 1, 1980

Feasibility is a value improvement process for projects. At any stage in project development, a feasibility study can be undertaken, but although the scope generally remains unchanged the extent of detail and level of accuracy usually increases with time. The main scope elements are a business definition, project description and an execution plan. The studies are designed to assess the potential of the project and to secure funding for on-going examination. Invariably, the investigations loop back to earlier stages to establish more appropriate development criteria but a critical stage is reached when a project construction decision is requested. This feasibility study requires very detailed presentation and analysis to a higher accuracy for the owner(s) and their potential lender(s).

Jan 1, 1997

A pilot plant has been constructed for the low temperature carboni-zation of Wallarah (N,S,W6) coal at the rate of 300 pounds per hour. The plant was built and tested at Australian Mineral Development Laboratories for Broken Hill Pty, Ltd. Char product was required within the specifi-cation 15.5 `S' 1 per cent volatile matter. The design was based c atz an entrained state carbonizer developed by Parry and U.S. Bureau of Mines co-workers at Denver, U.S.A. The method involved the carbonizatioan of fine coal by entrainment with air in an externally heated reactor.. The heat required for carbonization of tits coal was supplied to the be, both through the reactor walls and also by internal cambustion of products .

Jan 1, 1963

The paper deals with the problems of grouting methods for fissured-porous rock. The paper describes design procedure, injection process patterns and hydrodynamic testing techni- que to plan grouting programs for fissured-porous aquifers. A number of case histories is given to illustrate the imp- lementation of developed methodology at various mining pro- jects.

Jan 1, 1988

Thank you for that introduction and especially thank you to the organisers for inviting me. I've had a considerable interest in this area and I've had the advantage of an education from Neil on the subject of offering documents as a result of our collaboration together on the Securities Information Review Committee.

Jan 1, 1989

I.T.H. Drilling has been accepted as a tool used daily for both production and service work in Australian underground mines. For this reason, it is of interest to examine the rigs and drilling equipment in use to do this work, also to review the technique necessary to ensure that this drilling is done efficiently.

Jan 1, 1978

After a very brief historical survey and overall assessment of traffic requirements, the invitation by the British and French Governments for private groups to make proposals for a "fixed link" is described, and the resulting plethora of proposals is reviewed. The three schemes which gave some promise of being adequately backed by private finance are described as follows:

Jan 1, 1987

Interest in the sampling of refined copper cathodes has heightened over the last ten years. This has followed the increasing importance of cathodes as the principle trading form for metallic copper. It has also been given impetus by recent trends for quality certification of manufacturing inputs, specifically the AS3900 and IS09000 series of standards.

Jan 1, 1976

By E Ben-Dor, D Bakun-Mazor, Y Ben-Ari

Determining the mechanical properties of rocks is important for various civil engineering fields, including the mining of raw materials for aggregates used in the construction and paving industries. Traditionally, the mechanical properties of rocks are obtained through in situ and laboratory tests during geotechnical surveys. However, these time-consuming surveys involve many resources. In contrast, hyperspectral remote sensing methods make it possible to identify the mineralogical composition and crystallographic structure of the rock; properties that control the mechanical properties of the rocks. In this work, we characterise the mechanical properties of carbonate rocks by using a hyperspectral sensor in laboratory conditions. We collected about 150 cylindrical samples of carbonate rock, with a wide range of strength values from several rock outcrops in Israel. We used a point spectrometer in the range of 0.4–2.5 μm and a spectral image sensor in the range of 3.0–12.0 μm, scanning the samples to obtain the signature of their light reflections and spectral emissivity. We then measured the samples’ density, porosity, water absorption, and uniaxial compressive strength (UCS). We used sophisticated data mining to find statistical relationships between the hyperspectral signatures of the samples and their mechanical properties. We used this data to identify the most dominant wavelengths for predicting mechanical properties. We found that the density, porosity, and water absorption of carbonate rocks could be confidently predicted based on spectroscopy data, while the UCS of the rock could also be predicted, but less significantly. The results of the study pave the way for the development of measuring tools for the mechanical properties of rock, based on non-destructive tests of quarrying materials.

Nov 29, 2022

As an environmental "pollutant", noise is different. For one thing, it is localised (as opposed to transfrontier) and, for another, relatively low levels can trigger very strong human reaction. The reactions, which are annoyance-based, range from mild to violent and do not always correlate well with the levels experienced. This paper draws on technical aspects of noise to consider control and control principles and balances them with the subjective nature of the perceptions and reactions. It is critical to bear in mind that health effects resulting from noise are secondary to the primary human reaction. It is also important to appreciate that annoying noise levels are usually well below those which cause hearing loss. Large mines tend to be remote from cities and towns and the country surrounding such mine sites is often inhospitable. In general, residences near large mines are committed for use by mine personnel and annoyance from mining noise would be rare. Noise problems at long term operations are often a result of secondary activity or land use. As a pioneer mining community develops, secondary and service industries may be established and a township created. With changes in way of life, the perception of problems also changes. Therefore, it is never too early to plan for noise abatement, particularly because noise is only one of a number of environmental and community concerns. Ihny environmental problems are associat- ed with development or expansion of smaller open cut facilities such as hardrock quarries. There is an ever-present need to reduce product cost by mining or quarrying deposits close to the end user and many local authorities have to operate quarries for undertaking their civil engineering responsibilities.

Jan 1, 1987

By Somerville M, Muray A, Bocking M

Australia has an extremely large total hot dry rock (HDR) resource above a depth of 5 km, equivalent to 7500 times its present annual energy consumption, of which 80 per cent underlies the Great Artesian Basin. The resources most likely to be exploited first are those residing in homogeneous granitic bodies beneath sedimentary basins containing insulating rocks such as shales and coal measures. In the Sydney Basin south of Muswellbrook, an area of high geothermal gradient corresponds to a gravity low thought to be a buried granite body at a temperature of possibly 250¦C. This locality is suspected to have the ideal geological characteristics for Australia's first hot rock test facility. Australia's high HDR potential is possibly unique in the world, in that the potential sites satisfy four independent, geological conditions, each considered as favourable for the creation of a resource, and for the ease of extracting that resource. They are: ò Higher crustal heat generating capacity than that of normal continental crust. ò Much of the Australian continent is covered by sedimentary basins which contain a high proportion of shales and coal measures that have low thermal conductivities, thus providing an insulating blanket for the heat being generated beneath. ò The sedimentary basins are in many places underlain by large untectonised granitic bodies that are not only a major contributor to heat generation, but also ideally suited to the establishment of HDR reservoirs. ò The crustal shortening stress field that is found in the majority of the Australian continental crust results in a vertical minimum principal stress orientation which should result in the development of favourably oriented horizontal stimulation cells necessary for maximising an HDR resource.

Jan 1, 1995

Environmental leaching methods such as the toxicity characteristic leaching procedure (TCLP) test or the ASLP test are used to assess wastes including mining and mineral processing by-products. These tests were initially designed as regulatory tests simulating conditions in a co-disposal municipal landfill waste facility and do not allow leaching performance to be predicted in site specific scenarios. Further, the assumptions underlying these tests tend to define worst-case scenario leaching conditions for by-products from the mineral industry disposed of outside a co-disposal scenario.   Recently some characterisation leaching test methods have been issued as ISO/TS standards (ISO/TS 21268-3:2007 and ISO/TS 21268-4:2007) that aim to define the leaching performance of soil type wastes and to predict the leaching performance of these wastes over long time frames. In this preliminary work these standards are trialled for by-products from the mineral industry and the quality of information that can be obtained from them compared to TCLP/ASLP tests.   Where clear comparisons were possible, the TCLP/ASLP tests were typically found to extract a similar, or often greater, amount of component than (i) tests conducted at the same pH but without the acetate buffer or (ii) for test conditions aimed at simulating long-term leaching in an eluate defined by the waste type. While further work is required, the preliminary results indicated that the tests may provide reliable long-term estimates of leaching performance of wastes in soil types of variable pH and provide a suitable basis for long-term planning for optimal waste handling, treatment or even re-use.

Jun 1, 2010

Magnetic Separators have a wide application in dry separation processes, frequently in conjunction with High Tension Separation. Dry processes can frequently be superior to established processes in more commonplace mineral associations. A system of dynamics is postulated and the forces operating ar'e examined, together with a method of evaluating the effect of operating variables. Practical applications of these theories to obtain optimum results on an individual separator, and various separations using a laboratoryroll type separator are described.Practical Flowsheets are of two main types, the first consisting of a series of scalping operations, the second for rougher, cleaner, and scavenger operations with middling recirculation. Some common separation problems with certain mineral associations illustrate the need for different approaches for different mineral associations. A table of mineral separation characteristics is appended, from which amenability may be tentatively estimated.INTRODUCTIONMagnetic separators are widely used, either alone or in conjunction with other wet and dry concentration devices, for the upgrading of a variety of minerals. The high standards of efficiency attainable in dry mills, together with reduced operating and labour costs, are slowly becoming apparent in a wide variety of plants. The combination of wet and dry concentration plant familiar in beach sand mining is finding application for such processes as upgrading a crushed chromite product, and production of clean scheelite,cassiterite, and other concentrates. Other dry beneficiation processes (such as the high tension beneficiation of iron ore, and the benefiGiation of asbestos) avoid the use of wet processes completely.Dry separation processes are likely to be applied more widely as their possibilities become more generally known.

Jan 1, 1958

By D Macklin, R Hammond, T G. Blenkinsop

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Base metal sulfides at the Currawong volcanic-hosted massive sulfide deposit in the Lachlan fold belt of Victoria, south-east Australia, were formed in the late Silurian, but D2 deformation of the deposit in the Devonian Bindian orogeny was responsible for structural repetition that created the resource. The primary sulfide lenses were stacked by reverse-sense shear zones within a volcano-sedimentary sequence dominated by dacitic intrusions and turbidites. Shear zones were localised along lithological contacts, including the margins of the sulfide lenses. The competent dacitic intrusions did not fold during D2; folding was restricted to the packages of metasedimentary rocks. Overturning occurs within, but not between, the metasedimentary packages. The overall geometry of the deposit is that of a duplex, but the detailed shape does not conform to idealised duplex types, probably because of post-D2 deformation. A significant complicating factor for understanding the deposit, and for resource evaluation, is the dramatic variation in deposit geometry along strike, which may also be due to post-D2 deformation. The present day configuration of the deposit results from constructive thrust repetition of what may have been a single ore lens and destructive along-strike disruption controlled by rheology.CITATION:Blenkinsop, T G, Macklin, D and Hammond, R, 2015. Rheological controls on the geometry of the Currawong volcanic-hosted massive sulfide deposit, Lachlan fold belt, Victoria, south-east Australia, in Proceedings PACRIM 2015 Congress, pp 469–474 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By E Taylor, F Lebbing

The $2.5 billion EastLink project is a 39 km tollway and includes twin three-lane, 1.5 km long, undrained driven tunnels with cross passages every 120 m. The hard rock tunnels are being built to avoid passing the motorway through the Mullum Mullum Valley and help preserve the unique flora and fauna in the area. The design of the permanent concrete lining and waterproofing system for the EastLink tunnels was both innovative and practical, to meet the demanding environmental and production constraints of AustraliaÆs largest road project. This paper describes several key aspects of the tunnel design and construction, including: design of fully tanked, permanent concrete tunnel linings for the main tunnels and cross passages to withstand 37 m head of water pressure in combination with potential rock loading in the future;optimisation of the tunnel shape to minimise the amount of reinforcement required and the design of special welded mesh which was developed within manufacturing constraints;100 year design life and durability considerations in every aspect and detail of the design including concrete mix design and stray current mitigation;development of a precast invert solution for the main tunnel permanent concrete lining to enable faster lining construction and to minimise risks to the tunnel membrane associated with fixing reinforcement and construction traffic;development of prefabricated reinforcement details for the junctions between the main tunnels and the cross passages to enable faster construction and minimise risks to the membrane associated with fixing reinforcement; andincorporating the tunnel drainage sump at the lowest cross passage in the alignment, resulting in deep excavation to satisfy the required storage volumes for drainage.

Jan 1, 2008

Parallel lenticular orebodies occurring at the C.S.A. mine of Cobar Mines Pty. Ltd. are mined by mechanized cut and fill stoping over the full strike length. Access is provided for each stope lift from an inclined drive adjacent to the orebody. Mobile drill jumbos mounting hydraulically-operated booms are used for drilling upholes which are subsequently charged with ANFO explosive.Close control of drilling has been found essential for good back conditions and to ensure optimum fragmentation.Broken ore is transported from the face to the main ore pass by rubber-tyred, diesel-powered, load-haul-dump units. Initially, the units trammed ore to the main pass via the incline drive. As the stopes advanced and the lead distances increased, stope passes were developed in the wall rock and raised concurrently with each stoping lift. The passes terminate in drawpoints and production loaders are used to transport ore from the drawpoints to the main ore pass system.Two parallel ore pass systems have been developed to cater for both copper and copper-zinc ores. These systems terminate above a 48 in. by 60 in. jaw crusher. The crushed ore is conveyed to a traversing rock box and thence to one of two crushed ore bins adjacent to the main hoisting shaft. A loading station conveyor is interlocked with the winder to provide automatic ore hoisting.All phases of ore handling have been mechanized as completely as possible. Results to date indicate this policy has been vindicated but highlight the need for tight operating control and close liaison between operating and maintenance personnel.

Jan 1, 1969