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By B Lindqui, M V. Knyazev, L S. Tsemekhman

Gipronickel Institute JS that is a Research and Development Centre affiliated to the worldclass Norilsk Nickel Mining and Metallurgical Company, and Outokumpu Technologies AB (Boliden Contech AB) have jointly developed the reconstruction project of Pechenganickel metallurgical operations using a two-zone Vanyukov furnace. The international expert group appointed by the Nordic Investment Bank has examined the project. The project financing should be partly executed by the Norway government. Current annual rate of sulfur dioxide emissions is 100 000 t. The aim of the project is to reduce it to 12 000 tpy. Pechenganickel Combine is owned by MMC Norilsk Nickel. Currently it produces nickel high-grade matte from sulfide copper-nickel concentrate with up to ten per cent MgO content. The existing production is in accordance with the following flow sheet: agglomeration û electric furnace smelting with matte production û converting in horizontal converters. Annual production capacity is about 36 000 t of nickel in high-grade matte. Converter gases report to sulfuric acid production. The principal results of studies on high magnesia materials smelting in two-zone Vanyukov furnace, engineering solutions, and technical and economical parameters are offered.

Jan 1, 2004

By L O. Filippov, I V. Filippova

Subsea massive sulfide deposits have particular mineralogical compositions and textural features differentiating them from onshore ore. When extracted from salty water and exposed to the air, massive sulfide samples strongly oxidise and soon become covered by thin layers of iron, copper and zinc-rich sulfates and oxides, as well as elemental sulfur. The textural properties vary according to the degree of maturity and the sample position within the hydrothermal deposit. Because of the variation of secondary mineralisation and porosity level, sea floor massive sulfides respond differently from terrestrial ore to processing methods. Froth flotation, commonly applied to separate all types of sulfides from the gangue minerals, is one possible treatment technique to process sea floor ore. Sulfide recovery rate is, in most cases, excellent (>90 per cent). However, separation of the various mineral phases is difficult to obtain even when applying known methods used for onshore ore. Moreover, the flotation behaviour decreases dramatically with time of conservation, even when the samples were stored in a confined environment. High pH range, which is a good way to depress pyrite and therefore to favour the flotation of copper and zinc sulfides, does not have the same effect on subsea ore. Consequently, careful flotation procedure should be elaborated to obtain efficient mineral separation for this specific marine ore.CITATION:Filippov, L O and Filippova, I V, 2015. Processing of subsea massive sulfide ores by flotation – similarity and features with terrestrial ores, in Proceedings Third International Future Mining Conference, pp 239–244 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

In classical drill and blast underground mining methods, especially narrow vein operations economic quantities of broken ore can be left behind following normal mucking operations on the stope floors. The ore left behind can have significant economic value and if not collected can be lost forever. This paper reviews techniques for cleaning this material from stopes that have been used in the past and reviews possible modern techniques that can be applied to ensure this valuable material is removed from the stopes.

Aug 1, 2010

Magnetic separation using particle rotation in a continuously rotating magnetic field offers very low to insignificant non-magnetic particle entrapment, and precise magnetic fractions. The precision of rotating magnetic field separations makes the method ideal for dry laboratory magnetic analysis work, where conventional laboratory magnetic separators can give misleading or uncertain data. The very low entrapment characteristics make the method ideal for entrapment-critical separations within the diamond exploration industry or in gold recovery. A single wet rotating magnetic field (RMF) unit is able to achieve a cleaner separation (at similar or better recovery rates) than a three-stage separation using conventional wet drum separators. The RMF separator is able to work effectively at particle sizes below 50 ¦m, and RMF separation could, at least in theory, be used down to single domain particle sizes. Rotating magnetic field (RMF) separation is carried out by magnetically spinning the particles at frequencies up to 300 Hz. The particle rotation itself may be used to roll the particles out of the separator. At angular velocities of 100 Hz, magnetic flocs are unable to form, and any entrapped particles are energetically expelled. In an RMF separator, the outer drum can be stationary while the inner magnet rotor rotates, allowing, for example, the injection of cleaning water underneath the separating magnetics to help remove small suspended non-magnetic particles.

Jan 1, 2000

Two significant TBM boreability predic- tion models are outlined. Predicted advance rates are compared with actual advance rates taken from twenty case histories. The results show that a simple low cost method that uses one machine parameter and one rock parameter compares very favourably with a high cost sophisticated method which also includes information regarding discontinuities in the rock mass. The effect of rock texture on drillability is also examined. A method of quantifying rock texture has been developed and is outlined. Experimental results show that the developed TEXTURE COEFFICIENT returns highly statisti- cally significant correlations with drilla- bility data in a wide range of rock types.

Jan 1, 1987

By Griffith L, Lama RD

West Cliff Colliery mines Bulli Seam occurring at a depth of approximately 480 m. The Seam is intersected by a number of small shear zones and faults. While the faults have caused displacement of the seam, the shear zones are strike-slip structures with small apparent displacement of seam. Outbursts at West Cliff Colliery occur while driving through these shear zones. Few outburst wave occurred where faults have been intersected. In the last 3 years, over one hundred outbursts have occurred at West Cliff Colliery. The size of outbursts varies from a small bump to exceeding 140 tonnes of coal. A number of studies have been undertaken at West Cliff Colliery to control outbursts and predict Outbursts in advance of workings. These include: geological investigations, microseismic techniques, gas adsorption studies and gas drainage. The investigations to date suggest that outbursts of gas at West Cliff Colliery are more a gas phenomenon similar to what occurs in overseas mines. The results of various investigations are reported. West Cliff Colliery is located in the mid- west of the southern coal fields of N.S.W.

Jan 1, 1980

Various aspects concerning gold are mentioned below. These have no common theme but suggest points of interest any one of which, if warranted, could lead to development later and elsewhere. 'High level' auriferous gravels The gold deposits of Victoria are commonly classified as being either primary or secondary. Most primary occurrences comprise gold present in quartz reefs, together with other lode-like occurrences in which gold is associated with various sulphides, with or without quartz. Secondary occurrences are derived by physical release of primary gold and subsequent concen- tration of it as a constituent of sediments. Secondary gold deposits may be themselves eroded so leading to third or even fourth generation gold.

Jan 1, 1982

IT is intended in this paper to present in broad outline to the members of the Institute a short account of the conditions and operations that constitute what is, variously known as Subterranean Warfare, Military Mining, or Tunnelling. Realizing ,the magnitude of the operations, and the varied and minute details met with in them on,the Western Front, it is the writer's intention to confine these notes to operations carried out by the First Australian Tunnelling Company. In so doing there is no wish to detract from the very fine records of the Second and Third companies it is to be hoped that members of the Institute (or others) who were with these companies will write accounts of their doings-the former in the water-logged areas to the south of Armentieres, and later in the sand-dunes at Lombardzee, and the latter in the chalk area of the Lens coal...

Jan 1, 1920

The Manto Verde copper mine (Atacama Region, Chile) is due to go into production in 1996. It will produce 40 000 tonne/year of copper cathode by heap leaching/SX-EW. Mineralogical studies were undertaken in conjunction with the metallurgical testwork program to characterise the ore and its response to leaching by dilute sulphuric acid. The leachable copper mineralogy is dominated by the oxide copper minerals: brochantite and malachite with minor chrysocolla and atacamite. The gangue minerals include abundant orthoclase, specularite, quartz and chlorite with minor muscovite and trace smectite clay, calcite and limonite. The study showed that complete or partial decomposition of calcite, chlorite, smectite and wad consumed acid and generated solution impurities (Ca2+, Fe2+, Mg2+, A13+, K+, Si4+ and Mn4+2+ ). Although these were manageable at Manto Verde, their uncontrolled build-up could have affected the operation in several ways: the degradation of heap penneability and fonnation of crud in the SX plant from the precipitation of gypsum, goethite, colloidal silica and jarosite; and the entrainment of contaminated pregnant leach solution in the SX organic resulting in the transfer of impurities to the electrolyte and subsequent effects on cathode quality and electrowinning efficiency. In conclusion, process mineralogy played an important role in understanding and managing potential mineral-related problems in the heap leaching and SX-EW recovery of Manto Verde ore.

Jan 1, 1994

Geostatistical analysis, resource estimation and three-dimensional modelling of the gold grade distribution was undertaken using exploration drillhole data taken from the Mt Leyshon gold mine. The main aims of the project were to provide an independent estimate of the primary gold resource and to improve the estimate by better understanding the statistical distribution of gold and the establishment of more robust variograms. These criteria have been achieved by the removal of low grade sub-populations, increased sample size and access to data from the most recent drilling program. The outcome of this statistical study has led to a lowering of the sill and nugget variance of the variograms used. Distinct geometric anisotropy was identified in all the resource estimation zones and was used to model gold grade distribution.Two independent resource estimates were established from the primary gold resource, one based on a geostatistical estimator (kriging) and the other on a traditional estimator (inverse distance weighting). Both methods were compared with a contemporary kriged estimate by Mt Leyshon Gold Mines Ltd.

Jan 1, 1993

By Aylmore M. G

Samples have been taken from a two-stage industrial gold roaster treating a pyrite/pyrthotite/arsenopyrite concentrate, in order to describe the mineral- ogy, composition and surface area of the calcines. Sulfides oxidised to produce a porous magnetite in the first stage and a porous hematite in the second, pyrite predominantly roasted via a pyrrhotite intermediate. Sulfur was eliminated in both the first and second stages whereas arsenic was eliminated in the first but retained in the second, partly as rims on hematite particles. The finer sized particles from the cyclones and electrostatic precipitator, whilst having the greatest surface area, were the most refractory with respect to gold solubilization, probably as a result of incomplete decomposition (through short-circuiting) in the first stage, and through a combination of factors such as overheating and entrapment of sub-micro- scopic gold in the second stage.

Jan 1, 1991

By Hagen G, Uhlig H

In the Federal Republic of Germany the thermal environment in underground coal mines has deteriorated progressively over the past years. The number and capacity of refrigeration plants have increased correspondingly. In recent years high capacity spray coolers have been used in addition to conventional cooling coils.

Jan 1, 1988

By Lawson F

Synthetic calaverite (Au Tez) has been prepared and its physical properties checked.Simple flotation tests indicate that the recovery of calaverite should be possible using n-butyl or sec-butyl xanthate collectors under approximately pi I neutral conditions with a copper sulphate activator.Roasting calaverite in air at moderate temperatures resulted in its decomposition with the formation of elemental gold and tellurium dioxide.In alkaline oxygenated cyanide solutions, both gold and tellurium tend to dissolve. At pHs less than 14, about 50 per cent of the tellurium remains as elemental tellurium; however in very strongly alkaline solutions, essentially all of the tellurium is converted to the soluble tellurite ion (TeOl-).However, even at high pHs, the solubility of gold in the cyanide solution is still low due almost certainly to passivation effects.

Jan 1, 1991

By Eyers G. C

Long Shaft was initially developed using a rail haulage system on every working level comprising battery electric locomotives and granby trucks loaded by rail mounted rocker shovels. Production was commenced using conventional hand held cut and fill mining methods. In an effort to improve productivity and reduce operating costs a mechanised cut and fill stoping method evolved to suit the wider sections of the orebody. To further improve productivity and reduce costs the mechanised levels of the mine are progressively being redeveloped to enable the use of trackless diesel haulage equipment. An added benefit of trackless haulage equipment will be the ability to place development mullock into stopes as Fill.

Jan 1, 1988

By Gregory L. M, Phillips G. N

Although it has long been recognised that there is a diversity of minerals associated with Victorian gold deposits, the degree to which this mineralogy is systematic or haphazard has remained uncertain. Recent work by the authors and students under their supervision permits a sharp delineation of the boundaries between different mineralogical domains, and these are interpreted in terms of recent rapid advances in Victorian tectonics, and the regional framework of Victorian gold geology described in Phillips and Hughes (1996).

Jan 1, 1997

By Corbett GJ

Magmatic-related low sulphidation hydrothermal ore systems at plate margins exhibit distinct spatial and temporal zonations which can be used to aid mineral exploration and development. Low sulphidation systems at all crustal levels exhibit the same paragenetic sequence of events: early breccia formation, followed by quartz - secondary feldspar - sericite/illite veining, then mineralisation, and final argillic overprint. This sequence of events is interpreted to reflect the initial emplacement of melts at high crustal levels, and the progressive cooling of that melt and release of magmatic constituents into a circulating hydrothermal system.

Jan 1, 1995

By Barnes GJ

The gabbroid-hosted nickel sulphide deposits of the East Kimberley constitutes one of Australia's most prospective emerging nickel provinces. Sally Malay Nickel NL (SMN), a wholly owned subsidiary of Gindalbie Gold NL, has established the East Kimberley Nickel Project (EKNP). The EKNP project tenements cover about 2000 sq km. The tenements cover the northern potion of a corridor containing mineralised or potentially mineralised layered mafic-ultramafic intrusions which includes the Ni-Cu-Co sulphide deposits at Sally Malay and Keller Creek. The Sally Malay deposit is located 225 km south-south-west of Kununurra (Figure 1). The sealed Great Northern Highway passes 3 km to the east of the deposit.

Jan 1, 1996

By Spottiswood DJ, Kelly EG, Bull WR

An empirical model of a 254mm water-only cyclone treating minus 17001im coal has been developed. The model includes the prediction of by-passing, SG50 corrected, water split and the use of a single equation forthe reduced performance curve of particles in the range 1700-106pm. Particles finer than 106pm did not separate according to specific gravity. Simulations using the model showed the water-only cyclone performance to be dependent more upon feed size distribution than washability when the feed contains high-ash fines, but that, with a deslimed feed, the yield and ash content of the over-flow should be controllable by altering feed rate or feed pulp density.

Jan 1, 1985

The Charters Towers goldfield in northeastern Queensland produced over 206 tonnes of gold from gold-quartz veins hosted by Mid-Palaeozoic granodiorite, tonalite, diorite and to a lesser extent amphibolite-grade meta-sedimentary schist and meta-igneous rock. Mineralisation occurs in grouped, moderately dipping shear zones with altered wallrock rafts and a complex network of quartz veins.Over 75 per cent of the production came from three main vein systems in the central goldfield: the Brilliant, Day Dawn and Towers Hill vein systems.The Brilliant vein system is hosted by undeformed tonalite and contains north-plunging oreshoots on a north-dipping main fissure and on shorter east-dripping hangingwall fissures. The Day Dawn vein system is localised along a north-dipping dyke at the contact of two deformed granitoids in a brittly reactivated mylonite, where horizontal oreshoot plunges may be related to the original megascopic undulations in that structure. The Towers Hill vein system is hosted in two granodiorite types and has multiple ore controls.Structural analysis indicates that the distribution of the oreshoots within the vein systems is variously controlled by the primary fabric and igneous contacts of the granitoid host rocks. Splaying, changes in dip, and fissure intersections are the main controls. The largest vein systems are both in reactivated shallow-dipping mylonite, or in fissures in younger undeformed granitoids. Each vein system lies in a separate structural domain, usually where older east-striking structures are preserved.

Jan 1, 1990

In June 1992, the High Court of Australia recognised native title of the Meriam people over parts of the Mer Island in the Torres Strait as a form of common law. The Court also indicated that native title may have survived European settlement of the mainland Australia where it had not been extinguished by Governments and Aboriginal people have maintained their traditional connection with the land. The decision meant that two systems of land law were seen as existing side by side in Australia: ò one which derived from grants from the Crown under laws passed by Parliament; ò another which derived from the diverse laws and customs of the many Aboriginal groups in Australia.

Jan 1, 1996