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By Peeler P. K

The recent renewal of interest in hydrometallurgical routes for copper production has been brought about by the possible future reliance on mixed ores and lower grade deposits, environmental aspects, and energy considerations.A number of hydrometallurgical processes for the recovery of copper have recently been proposed. Flowsheets are developed for two processes which incorporate several treatment methods being experimentally studied in Australia.In the first process a cupric chloride leach is followed by electrowinning whilst the second is based on the formation of cuprous ions, stabuized by acetonitrile and subsequent disproportionation to cupric ions and metallic copper. For the purpose of comparison, flowsheets were also developed for the Arbiter and Cymet processes.Process economics are estimated for the four processes and the results are discussed in relation to competitive pyrometallurgy. None of the four hydrometallurgical processes, with possible exception of the Cymet process, appears to be competitive with established large scale and newly developed pyrometallurgical processes for chalcopyrite.However, because the economics of the individual hydrometallurgical processes depend strongly on specific conditions, a "tailored" process may be competitive with pyrometallurgy in particular circumstances.

Jan 1, 1977

Sulphuric acid leaching at atmospheric pressure of a number of Australian nickeliferous laterites was examined in detail. The results obtained indicate that nickel can be extracted from these ores, although the conditions required to achieve about 90 per cent extraction vary widely. These differences in reactivity can be related to the types of nickel-bearing minerals present.Nickel is more readily extracted from nickel-bearing clays such as chlorite, than it is from nickel-containing goethite.The results clearly show the problems associated with the processing of complex ores such as the nickeliferous laterites, and they indicate the need for complete characterization of each deposit.

Jan 1, 1978

Declining from surface provides access, haulageway, ventilation and provision for ser- vices for stoping and development. Three boom jumbos and 3.8 m3 capacity diesel loaders are used in decline development, the majority of which is driven at a gradient of 1 in 9. Primary ventilation is drawn from the mine through raisebored airways and high pressure contra rotating fans provide secondary ventil- ation. To meet schedules a special decline crew was formed on similar lines to a mining con- tractor. The basis of payment for the mining party was changed and the net effect was to accelerate development. Ground conditions demand constant support and this is achieved with chemical anchor rock bolts, multistrand grouted bolts and shotcrete. Major local shear zones are encountered and when they are to be driven through, a combina- tion of the above methods, involving a spiling technique, is used.

Jan 1, 1977

By M P. Simpson

Forty one whole rock samples from the Gold Cross low-sulfidation epithermal Au-Ag deposit have d18O values that range from 4.4 to 9.3 per mil, with an average value of 7.0 per mil. Unaltered and weakly altered rocks have d18O values greater than eight per mil, and the orebody is surrounded by samples that are depleted in 18O. A strongly silicified sample adjacent to the Empire Vein System has a d18O value of 9.0 per mil, similar to previously reported analyses of vein quartz (7.0 to 11.7ë, average 9.4ë). This suggests that, in detail, Golden Cross may have a zone of 18O-enriched wall rocks in the core of the deposit, adjacent to the main underground veins. Although some workers have suggested that stable isotope geochemistry may provide useful information for epithermal mineral deposit exploration, at Golden Cross this is not the case. Alteration minerals, major elements and trace elements all define larger, less ambiguous halos than the zone of 18O-depleted wall rocks.

Jan 1, 2001

Mining is taking place at increasing depths of cover on the Southern Coalfield beneath predominantly massive sandstone strata. Within the next twenty years, there will be longwall mining at depths greater than 600 m. As the Sydney Metropolitan area continues to expand and as coal mining approaches these urban areas subsidence will continue to become an increasinglY important aspect of coal mining research. Investigations, commenced in the mid 1960's, allow prediction of subsidence in the Southern Coalheld with reasonable confidence. The work is showing that the characteristics of thc subsidence troughs over the deeper mining at Appin differ from the characteristics of mine subsidence at less cover.The longwall mining at Appin Colliery has resulted in a maximum measured subsidenee of 730 mm. The maximum strains were small because of the large radii of curvature of the subsidence profiles. There was no damage to any of the buildings in the township of Appin.

Jan 1, 1982

A study of the accessory opaque iron-titanium oxide minerals of the Oiles Complex, central Australia, was an Important complement to an investigation of the magnetic properties of the Complex. These minerals constitute no more than 10 per cent of the rocks sampled, and generally less than 1 per cent of the ultramafic rocks ("magnetite" concentrations were not sampled for magnetic investigation).Titanomagnetite is the main opaque mineral present, although ilmenite exsolution has been widely developed. High-temperature oxidation of these produced mainly titanohematite, pseudobrookite and rutile. Both exsolution and high-temperature oxidation developed along specific crystallographic directions (along {111}), and in Irregular patches. Low-temperature oxidation is generally not well-developed, indicating the small degree of weathering in the rocks sampled.Although the Oiles Complex is layered, no apparent overall preferred orientation of the iron-titanium oxide minerals was observed, other than crystallographically controlled alignment of very fine grains within pyroxene crystals. Other textural features of the opaque oxides are restricted to symplectic intergrowths mainly with the ferromagnesian silicates.

Jan 1, 1971

By Skinner A. J, Thoman B. C

The general structure of microprocessors and their method of use is described, and de- tails given of their application in two parti- cular examples of instrumentation for mineral concentrators. One is in a pulp density gauge, and using this example, the way in which a microprocessor-based unit can be made to be self-calibrating is described. The other is in an on-stream analysis detector for uranium in solvent, where a microprocessor is used to re- place a mini-computer.

Jan 1, 1977

By Xu Z, Hu C

An attempt has been made to investigate the performance of green pellet formation of the Daye magnetite concentrate from the weak-magnetic separation plant. The optimum conditions for the commercial production of green pellets was found through experimental research. The satisfactory size range for balling is 75 ¦ 3 per cent -200 mesh. The suitable moisture content is between 8.7 and 9.1 per cent and the optimum amount of bentonite added is between 1.5 and 2.5 per cent. The emphasis is on the size of the feed materials since the grinding fineness, which can be obtained at the plant, at most is 78 per cent -200 mesh. If the optimum fineness for the pellet formation is above this value, this means that the concentrate must be re-ground before balling. The results from experiments showed that a good quality green pellet can be attained by using materials below 78 per cent -200 mesh, which provides a strong foundation for the commercial production of green pellets.

Jan 1, 1999

By H Firdausi, I Pasek, T Chenier

The Grasberg Block Cave (GBC) Mine is one of the future underground mines of PT Freeport Indonesia (PTFI). Located in the remote highlands of Papua, Indonesia, the GBC mine is scheduled to start production in 2017 reaching its peak production capacity of 160 000 t/d in 2023.In order to reach planned production capacity, the GBC mine will utilise an ore handling system consisting of rail haulage, crushing and conveying. The rail haulage system will utilise over 20 km of track while crushing is accomplished by way of three gyratory crushers each with a capacity of 3300 t/h. Nine conveyors operating in two parallel systems, each system over 3 km in length, will move the ore from the crushers to the stockpiles. These systems require a network of larger tunnels and mass excavations to accommodate the planned production facilities.This paper will describe the ore handling system, tunnel and mass excavation methodology as well as some of the challenges encountered with ground conditions and excavation quality during the execution of the project. A combination of lateral and vertical development methodologies and equipment, including drill jumbos, mechanised raise climbers and specialised ground support equipment, have proven successful in the development of a quality ore handling system.CITATION:Pasek, I, Firdausi, H and Chenier, T, 2016. Development of the ore handling system at the Grasberg block cave mine, Indonesia, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 599–608 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

This paper contains an account of some creep tests on electrolytic lead and some of its alloys. The stresses used in determining creep were 500, 350, and 200 lb. per sq.' in. The alloys contained silver, bismuth, tellurium, antimony and zinc respectively. All were castin vacuo, and tested "as rolled." Tests were done also on electrolytic lead which had been cast in air.The electrolytic lead contained 0.0005% total impurities.The preparation and vacuum casting of this lead have been described in a previous paper in this series. The preparation of the alloys, and the air casting of the electrolytic lead, are described in the next section.EXPERIMENTAL PROCEDURE.Every effort was made to keep the vacuum-cast specimens from contact with the atmosphere throughout their history.The ingots were stored eIther in a vacuum desiccator or immersed in heavy oil. The creep specimens were coated with vaseline except during rolling, etching and photography, which involved exposure to the atmosphere for about 45 minutes all told.It is not claimed that vaseline is a perfect shield against the intrusion of atmospheric gases. Possibly during the months that some tests were in progress the gases diffused through the vaseline and gained a limited access to the lead.Nevertheless, the use of vaseline gave protection that brought the tests nearer the ideal at which the author aimed, *Research Fellow, Dept. of Metallurgy, University of Melbourne.

Jan 1, 1936

By Fogarty J. G H

Ausmelt Technology has a unique capability of removing the impurities, phosphorus and sulphur, from the feed materials to the process. Sulphur is removed to the gas phase almost completely because of the interactions of ore and coal in the reaction region at the top surface of the slag bath. Phosphorus is removed to the slag phase, with both basic and higher, controlled iron oxide levels in slag being achieved in the process. The significance of these features of the process relate to the production of pig iron with very low levels of these impurities for the further processing to steel, and to the treatment of high phosphorus and high sulphur raw materials. The marketability of pig iron and the raw materials are discussed in relation to this feature of Auslron.

Jan 1, 1999

Mineral deposits of the central New Guinea region (Gunung Bijih, Ok Tedi, Mount Kare, Porgera, Frieda River) and of southeastern New Guinea (Wau-Edie Creek, Wafi, Hamata, Hidden Valley, Tolukuma, Misima) are associated with hot, forceful intrusions of magma of mantle origin that penetrated thick Precambrian and Palaeozoic continental crust. The interaction of high- temperature melt with continental crust, and the differentiation of melt while in transit through thick crust, may be factors in generating ore. Mineralised intrusives in central New Guinea are a result of Neogene- Quaternary magmatism and were emplaced in a foreland thrust belt environment, a setting similar to the (mineralised) Laramide intrusions of southwestern USA. In both cases, central New Guinea and the Laramide, magmatism is not obviously subduction- related. Mineralised intrusives in south- eastern New Guinea (Wau-Edie Creek, etc.), also, are in a thrust belt setting, and are not obviously subduction-related. The association of. gold in southeastern New Guinea with a second (Pliocene) phase of igneous activity, rather than with earlier (Miocene) activity suggests that re-working by successive intrusions may be a factor in localising ore. This is seen, also, in the Bismarck-Solomon islands region where the richer deposits are associated with later (Pliocene) intrusives rather than with earlier (Eocene-Oligocene) intrusives. Unlike the mainland mineral deposits, those of the Bismarck-Solomon islands are clearly subduction-related.

Jan 1, 1991

THE Taranaki oil-field is situated on the western side of the North Island of New Zealand, at about its widest part, and may be said to be the most compact and fertile part of the Dominion, for, with the exception of the upper half of Mount Egmont and of the ranges adjoining, which absorb 36,000 acres, the whole of the area, minus what is taken up by the rivers and streams is suitable for settlement, and certainly two-thirds is good land. The gross area of the district is 2,417,299 acres. The principle rivers are the Wanganui, Mokau, Waitara, Patea and Waiwakaiho. Mount Egmont, which is 8260 ft. high, used to be called Taranaki, and from it the district takes its name (the Maori meaning of which is "sloping peak ").THE OIL-FIELDThe discription of an oil-field now-a-days usually resolves itself into a mass of figures and statistics, of great interest and value to the engineer and commercial man, but practically indigestible to the general public. It is the realm of the financierand the captain of industry.

Jan 1, 1912

The offshore Maui gas/condensate field was discovered by Shell BP and Todd on Services Limited in 1969. Subsequent appraisal drilling and negotiations with the Government led to a development agreement, æThe Maui White Paper' being concluded in 1973. Part of this agreement provided for the Government to take a 50 per cent shareholding in the field. The field is comprised of a double domed anticlinal structure containing two gas reservoirs at depths ranging from 2700 - 3000 m. Water depth is 110 m. The development plan called for two standalone steel platforms to be installed sequentially over a period of some years depending on gas demand. The first platform (MPA) was put in place in 1976 but difficulties were experienced with piling and drilling of the 12 (later increased to 14) wells did not start until 1978. First gas was piped ashore late in 1979.

Jan 1, 1994

By M R. Stevens

An approach of geological mapping and descriptive criteria has been used to identify hydrothermal eruption breccias, named the Onemana Breccia. These in part mantle a gold bearing fossil hydrothermal system located on the eastern side of the Coromandel Peninsula, New Zealand. Whilst eruption breccias are documented from active and recent geothermal centres within the Taupo Volcanic Zone and in Northland their recognition at Onemana is the first confirmed discovery for this lithotype within ancient hydrothermal systems of the Coromandel Volcanic Zone. At Onemana the widespread occurrence of silicification, sinters, volcanic lake sediments, eruption breccias and advanced argillic alteration allows classic hot spring epithermal modelling. The geological setting, distribution, lithological characteristics, hydrothermal alteration and trace element geochemistry of the Onemana eruption breccias are described. These breccias are closely comparable with hydrothermal eruption deposits elsewhere, particularly those in active ore forming hydrothermal systems. Consideration is given specifically to the role of the Onemana Breccia in an exploration strategy for discovering epithermal gold-silver deposits.

Jan 1, 1991

A simple process for making filter aids from coal by controlled carbonization at 800-1200·C is described.Several possible variations in reactor design have been used experimentally, involving fluidized beds of carbon or inert material, reaction of the particles while entrained in air, and a combination of entrainment and fluidization.Product yields depend upon the composition of the parent coal but are always less than the sum of the ash and fixed carbon values determined by the proximate analysis. The product yield also depends on the air-to-coal ratio, which affects the amount of coal substance burned and the temperature attained. Particle residence time and reactor temperature affect the degree of devolatilization of the product and hence its wettability. The filtration behaviour of carbonaceous filter aids is greatly influenced by the size distribution, shape and physical properties of the particles-parameters which are largely determined by fue type and particle sizing of the coal used.Carbonaceous filter aids are distinctly different from other types commonly used and extensive industrial applications are anticipated in a wide range of industries ranging from food to mineral processing.

Jan 1, 1970

By D FitzGerald, S Jakica, R Paterson, J Silic

A new 2.5D airborne electromagnetic (AEM) algorithm has been developed by Intrepid Geophysics and Jovan Silic & Associates. The advantage of 2.5D (2D geology, 3D source) AEM inversion in 3D geological mapping applications and identification of conductive drilling targets, compared to the more commonly used conductivity-depth imaging (CDI) transforms or 1D inversions, are demonstrated using examples from banded iron formations (BIFs) and other geological settings. We show emerging AEM systems are capable of providing estimates of economic rock unit thicknesses, dips and fault definition at an accuracy that mitigates the need for pattern drilling.The 2.5D inversion application used in this work and described in Silic et al (2015) is a substantially changed version of ArjunAir (Wilson, Raiche and Sugeng, 2006), a product of CSIRO/AMIRA project P223F. The changes include a new forward model algorithm and a new inversion solver. The application enables the accurate simulation of 3D source excitation for full domain models inclusive of topography, non-conforming boundaries and very high resistivity contrasts. Solution is accurate for a geoelectrical cross-section, which is relatively constant along a strike length that exceeds the AEM system footprint.The major innovation includes a new inversion solver with adaptive regularisation, which allows the incorporation of a misfit to the reference model and the model smoothness function.Memory usage has been dramatically reduced and is estimated prior to execution. For speed the software has been parallelised using Intel message passing interface (MPI) and can be used on standard computing hardware or computing clusters. Data from survey lines with lengths exceeding 100 km can be inverted on high end laptop computers.We allow flexibility in the selection of components and in the estimation of noise.AEM inversion examples are shown for surveys from BIFs, base metals (volcanogenic massive sulfides) and geological mapping projects and the results are compared with known geology and drilling. We demonstrate the much improved mapping and target definition delivered by this inversion method when compared with the other more common transforms or inversion methods used on these projects.CITATION:Paterson, R, Silic, J, FitzGerald, D and Jakica, S, 2017. High accuracy .D airborne electromagnetic inversion method for banded iron formation and other geological settings, in Proceedings Iron Ore 2017, pp 319–330 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Lyon R. J P

The quartz-cassiterite-wolfram veins at the Aberfoyle Tin Mine, north-eastern Tasmania, form a sheeted zone about 200 ft. wide and 1,600 ft. long in slightly contact metamorphosed shales, slates and greywackes, and are associated with a cupola of aplitic granite whose top is about 1,050 ft. below the present surface. Economic mineralization persists from the surface down to a vertical depth of 1,050 ft. to 1,100 ft., dying away in the vicinity of the cupola. Down to the 9-level there is a progressive increase in wolfram content of the veins, and a decline in cassiterite content, with increasing depth.The veins are banded or zoned, with a seivedge of muscovite on the wall. Cassiterite, wolfram and sphalerite occur inside the selvedges, projecting into a core of quartz of varying width. Other sulphides form the central part of some narrow veins, or occur as clots in the quartz. The general sequence of deposition of the ore minerals was: (1) cassiterite, wolfram; (2) arsenopyrite, pyrite, molybdenite; (3) pyrrhotite (in part); (4) blende-group minerals-chalcopyrite, sphalerite, stannite, pyrrhotite (in part)-as solid solutions; (5) galena, tetrahedrite, matildite, native bismuth, scheelite; (6) marcasite and secondary pyrite, magnetite and hematite. The sequence of deposition of the gangue minerals was: (1) fluorine-bearing minerals-muscovite topaz, apatite, triplite, fluorite-more or less contemporaneous with the cassiterite and wolfram;' (2) quartz-contemporaneous with the earlier sulphides; (3) carbonates--contemporaneous with the later sulphides. The stages overlapped somewhat.The composition of the sphalerite and heat treatment experiments with the solid solutions indicate that the blende-group sulphides were deposited at about 6000 C., and cooled rapidly, so that unmixing of the solid solutions was arrested. This accords with the likelihood that the country rock temperature was not above 2000 C. Annealing experiments at between 3500 C. and 6000 C. led to further precipitation from solid solution at the lower temperatures, and to significant segregation by solid diffusion within, a week, indicating that both deposition and cooling of the ore were rapid processes-completed in a matter of days. Since the mineralizing solutions must have lost some heat during...

Jan 1, 1957

By J Dwyer, M Hill

Downer’s mining division has made an operational and financial commitment to developing engineered solutions that mitigate the risks associated with operator proximity to uncontrolled development drill boom movements, and unguarded rotating drill steels.With the potential for serious injury or fatality, these identified risks are categorised as critical. Previous attempts by the industry to engineer them out have produced limited success, with numerous incidents still occurring year on year. Ultimately, the industry (as a whole) remains reliant on procedural prevention for operator safety.Downer understood the success of such an initiative would largely depend on the effective collaboration between operational experience, technology experts and automation. With so many variables requiring consideration; such as physical operator movement, machine boom movements, variable machine positions, and underground environmental impacts – challenging traditional technologies was necessary to deliver an optimal solution.For that reason, discrete detection (similar to laser curtains or beams) was considered not fit for purpose. The use of situational mapping, using rotating lasers, however, provided the optimal solution. The lasers collect data that is then processed using a custom software application.The software application is specifically programmed for tracking and classifying objects within detection zones, using advanced algorithms and filtering. Recognition and removal of non-positive disturbances are possible without losing personnel detection capability. The detection of relevant classified objects (humans) is determined by analysis of object size, age, movement, and speed etc. When the relevant object is detected, an alarm and inhibit function is applied preventing drilling functions.Any breach of the safety zone (forward of the front jacks) will automatically disable the hydraulic boom function. This can only be reset in the cabin once the person or persons have returned past the front jacks of the development drill into the safety zone.Downer, in collaboration with partner YUMARR Automation, has successfully developed this reliable boom isolation system, and is called JumboGuard. The system has now been commissioned and installed across all Downer Mining development drill fleets, operating in Australia.CITATION:Hill, M and Dwyer, J, 2017. JumboGuard – automatic boom isolation system, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 287–294 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

The Mount Angelo prospect outcrops as two copper rich gossans, the larger of which is 250 ft long and 70 ftwide. The mineralization is epigenetic and replaces part of a brecciated and disturbed lime tone and calcareou sediment sequence.Magnetic and self potential survey indicated a substantial body of sulphide mineralization, the top of which was approximately 100 ft below the surface.Diamond drilling confirmed this and established the presence of a mineral body of at least 500,000 tons, extending to a depth of 300 ft. Of the 500,000 tons, 200,000 ton are primary copper ore which a ays 2 per cent copper.This mineral body is not economic at present, but could become economic if copper mining is established elsewhere in the district...

Jan 1, 1966