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There are no large rivers in Western Australia capable of supplying water for processing magnetite ores. If sea water is used there are severe corrosion issues and the requirement to wash the concentrates with potable water. If groundwater is used there is a need to treat the water and sustainability is an issue for large projects because of potential drawdown of the aquifer.If sea water is desalinated the cost of the water is high because of the power requirement. At the same time the necessity to conserve water has lead to flow sheets where all of the tailings have to be filtered to minimise the water requirement.Managing the various water qualities and optimising water recovery and quality has resulted in optimising the water balance and issues meeting environmental obligations. Reverse flotation is a critical final step in reducing the silica level in the final concentrate and requires good quality water.

Jan 1, 2009

By Burns W. G, Muceniekas E, Whitcher I. G, Hughes F. E

No iron ore deposits were reported before 1961 from the Hamersley Ranges, Western Australia, although low-grade bedded iron formations, associated with ferruginous jaspers and cherts, were known to occur in the local Nullagine Series of Precambrian age.In January-March 1961 preliminary investigations in the area drained by the Turner River, Duck Creek and Serpentine Creek revealed the presence of over 1000 million tons of dense botryoidal or pisolitic limonite, forming flat-lying orebodies with 50-57 per cent iron.Large bedded hematitic orebodies were also discovered in the same area in August-October 1961. These have a porous, biscuity texture and an iron content of 60-61 per cent. They occur at a welldefined stratigraphic level (Brockman Iron Formation), normally in synclines where they have been upgraded by circulating meteoric waters during an old cycle erosion.In 1962 systematic geological studies and mapping, together with sampling and scout drilling, indicated larger reserves of biscuity hematitic ore and led to the discovery of massive hematite deposits at Mt. Tom Price. These were extensively drilled in 1963, proving the persistence of' high-grade mineralisation to a depth of 200 ft and over.To date the total indicated reserves of the Hamersley deposits, within the area held by Hamersley Iron Pty. Limited, are of the order of 4960 million tons and thus rank among the more important of the world. The reserves are composed of 600 million tons of bedded dense hematite ore with 64-66 per cent iron, 2900 million tons of bedded biscuity hematite-limonite with 60-61 per cent iron, 1360 million tons of limonite (goethite) ranging in grade from 50 to 57 per cent, and 100 million tons of canga (conglomerate) iron ore containing 53-63 per cent iron. In all cases harmful impurities are comparatively low.

Jan 1, 1964

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

By Prasad S, Chatterjee S. S, Singh B. N

The chief source of metallic iron for steelmaking in India, even today, as it is in most part of the world, is through blast furnace (BF) route. This will continue to be so in the foreseeable future as the technology is most efficient, both process and economy-wise. However, as the world is moving into the next millennium, a critical look is being given to the process primarily because of its non-ecofriendliness (as a result of extensive use of metallurgical coal/coke requiring elaborate pollution control facilities) and huge investment involved for supporting facilities like extensive raw material preparation and handling, agglomeration, adoption of sophisticated instrumentation and control system, etc.

Jan 1, 1999

By Branagan D. F

The geology of the area studied is briefly described, together with the prospecting methods used in the search for copper, lead, zinc and uranium ore bodies.Four prospects, Mt. Corella, Yanasinga, Lawlor's and Greenmount, which were diamond-drilled, are described in detail and geochemical results are discussed in relation to the mineralization found. Copper anomalies were found wherever intrusive rocks were mapped, and showed a much closer relation to geology and mineralization than did the predominantly lead and zinc anomalies.Geochemical prospecting aids in the overall mineral search programme because of its speed and economy, as it helps to pinpoint areas worthy of detailed geological examination. Geochemical anomalies are a guide to favourable zones but may not indicate the presence of ore.INTRODUCTIONDuring 1953-55 the National Lead Company of New York carried out a search for minerals in an area south and west of Cloncurry (Fig. 1) in rocks of Precambrian age. After reconnaissance mapping, a number of prospects were chosen for closer examination by detailed geological mapping and geochemical sampling, and from these prospects, five sites were selected for drilling.This paper records the salient features of the exploration programme and discusses the geology and geochemistry of four of the prospects-Mt. Corella, Yanasinga, Lawlor's and Greenmount. Practically all the prospects examined showed high zinc "anomalies" or "dispersion" trains. Greta, Mt. Corella and Lawlor's prospects showed some copper anomalies and, to a lesser extent, lead anomalies. In particular, Greenmount exhibited striking copper anomalies.

Jan 1, 1960

Geophysical methods are useful non-invasive means of collecting subsurface information on the environmental impacts of resource developments. Techniques such as seismic refraction, ground probing radar and magnetics are well established tools for environmental studies of waste disposal sites. Repeat resistivity surveys, gravity surveys, and infrared or multispectral remote sensing hold great promise for monitoring environmental changes. Examples from New Zealand include geothermal field monitoring, which may involve the use of geophysics for .detecting changes of surface thermal activity, hydrothermal eruptions, induced earthquakes, contamination or depletion of shallow groundwater, and subsurface fluid recharge. Other examples include resistivity monitoring of contained effluent disposal ponds, tailings dams and landfills. Experience has shown that care is necessary to identify the natural variability of the parameter measured before drawing conclusions regarding an observed change.

Jan 1, 1994

By Green P. F

Apatite Fission Track Analysis (AFTA) is a thermal history reconstruction tool that enables determination of magnitude and timing of maximum paleotemperature and paleo-geothermal gradient at the time of maximum paleotemperatures. From this information, the amount of section missing at major unconfornities can be estimated and incorporated into basin models. The Gippsland Basin has a number of distinct problems that can be tackled using AFTA. 1. The nature of the regional break between the Late Cretaceous-Tertiary Latrobe Group and the underlying Early Cretaceous Strzelecki Group. 2. The tectonic history of the basement flanking the basin and its effect on sediment composition. 3. The age of igneous activity in the basin, as typified by the widespread basaltic plugs and dykes intruding the outcropping Strzelecki Group. Major uplift and erosion within, and adjacent to, the early Cretaceous rift basin in the Mid-Cretaceous, at -95 to 100 Ma, initially constrained the Latrobe Group depositional area to the central deep of the Gippsland Basin and provided an elevated source of quartz-rich detritus for the Latrobe Group reservoirs. This is in marked contrast to the preceding period in the early Cretaceous when contemporaneous volcanism dominated as a source of detritus, producing quartz-poor lithic sandstones, in which a host of attendant diagenetic reactions destroyed their reservoir potential. Initial uplift and erosion of the volcanogenic Strzelecki Group also occurred in the mid-Cretaceous as revealed by a number of distinct inversion structures, and erosion of this material will have locally provided very poor quality sand to the basal Latrobe Group.

Jan 1, 1992

The concept of a magnetic hydro-cyclone is undeveloped, possibly because studies by Bragard (1965) and the Royal School of Mines in London (Robinson, 1965) were not encouraging. Its role for the concentration of ironsands is attractive in that the classifying effect within a hydrocyclone may be comparable to the classifying effect in the gravity concentration of ironsands, and thus two steps may be achieved in one. Furthermore it should be a very simple and cheap process. The idea has been explored intermittently since 1976 but more energetically since the offering of a magnetic hydro-cyclone thickener by Boxmag Rapid (1983). This paper summarises the development and test work which are detailed elsewhere (Fricker, 1984).

Jan 1, 1984

By D O. Hayba

Metal-rich slurries discharged from excess-enthalpy geothermal wells at Kawerau (NZ) indicate that an efficient ore precipitation mechanism operates in some feedzones. In our conceptual model, which takes into account the relative permeabilities of liquid and gas phases in boiling fluids, a metal-precipitating liquid phase is effectively immobilised along boiling fronts, leading to the formation of highly concentrated ore. Chemical equilibrium and heat/mass transport modelling demonstrate the general applicability of this conceptual model to hydrothermal eruption environments.

Jan 1, 1995

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

Rhyolitic rocks are volumetrically significant in the eastern part of the Coromandel gold province, yet deposits hosted by rhyolite (Kapowai, Broken Hills, Neavesville, Wharekirauponga and Waihi Beach) are generally low grade and subeconomic, especially compared with andesite-hosted deposits. In contrast, rhyolitic volcanic centres in Nevada host a number of economically significant epithermal gold deposits such as Round Mountain, Sleeper and Bullfrog. The Nevada deposits are associated with 27-20 Ma continental arc volcanics dominated by ignimbrites (eg Round Mountain), or younger 17-9 Ma bimodal rhyolite-basalt volcanism related to extensional basin-and-range tectonics (eg Sleeper). The Round Mountain deposit is localised on a caldera boundary fault and the mineralisation was deposited soon after eruption of the host rhyodacitic ignimbrite. In other Nevada deposits, hydrothermal systems are linked to the closing stages of flow-dome complexes and mineralisation is localised along normal faults associated with extensional basin-and-range tectonism. The style and composition of the mineralisation is similar in both the Coromandel and Nevada deposits and consists of sheeted and stockwork quartz veins, containing electrum as the main ore mineral and only minor sulphides (mainly pyrite) Likewise, the vein minerals were deposited from low salinity hydrothermal fluids in the temperature range of 200-270¦C. Both the Neavesville and Round Mountain deposits are geochemically anomalous in molybdenum. The deep oxidation of the Nevada gold deposits, dry climate and low level of competing land uses combine to make it economic to mine and process very low grade ore (0.2 - 2.0 g/t Au) by heap-leaching with cyanide solutions in most areas of Nevada. Although extensive low grade gold mineralisation is known at deposits such as Wharekirauponga and Neavesville, it is sub-economic because of shallow oxidation and land use conditions that are unfavourable for open pit mining and heap leaching.

Jan 1, 1996

THE power requirements of the Mount Lyell Mining and Railway Company at Queenstown, Tasmania, have, since the inception of smelting operations in June) 1896, been derived continuously from the extensive forests in the watershed of the Queen River, adjacent to the works, the fuewoodbeing of good quality, mainly composed of myrtle or beech (Fagus Ounninghami), eucalypts, and manuka (Leptospermum ericoides). The country is very rugged and mountainous, indented by numerous ravines and gullies, and intersected by, many creeks, which are subject to periodical floods, under the influence of a heavy and persistent rainfall, which averages about 110 in per annum. The areas so far exploited aggregate a total of about42 square miles, and this denuded country gives promise of ultimately becoming very valuable pastoral ground for cattle-raising. The tonnage of wood yielded per acre varies from 40 to 100 tons on stack measurement of 80 cubic feet per ton, 60 tons per acre being considered a good average yield. The gross amount...

Jan 1, 1910

Copper waste dump leaching is growing in importance because of the.large tonnages (up to 250,000 ton/day) of low grade waste rock available from open cut mining of copper deposits and proof that controlled leaching of copper from such dumps can be profitable.Overburden or waste rock, ranging in size from large boulders to fines, is dumped as cheaply as possible on sloping sites. Copper is leached from the dumps by applying up to 12,000 gal/min of leach solution (a combination of spent solution from cementation and make-up water) to the top of the dumps by various techniques.Efliuent from the dumps is sent to a cementation plant for copper recovery.Factors which may be controlled, either directly or indirectly, to give a controlled copper content in the dump efliuent (usually 1-2 g/l.) are the cycle of operations (i.e. the alternate wetting and drying periods), thevolume of solution applied to the dump, pH, Fe2+ and Fe3+ content or redox potential, oxygen content, bacteria and their necessary nutrients, and temperature.Dissolution of oxide copper minerals appears to be mainly a function of acid concentration. Copper sulphide minerals need oxidation for dissolution to occur and this is accomplished by a combination of oxygen,ferric ion, and bacteria. Oxidation of pyrite, oxidation of Fe2+ to Fe3 +, and hydrolysis of Fe3+ are of some importance in leaching practice. The presence of gangue carbonate minerals is detrimental.Physical factors connected with penetration of solution into large rocks are important and the treatment of an individual dump usually extends over a period of many years. Recovery of copper from solution is usually achieved by cementation with iron (usually in the form of crumpled cans) but the use of sponge iron is becoming more important. Iron consumption varies from 1 to 4 lbiron per pound of copper. Preconcentration of the copper in the efliuent solution by solvent extraction followed by electrolysis may become a useful method.Application of dump leaching techniques to metals other than copper depends on finding an economic method of recovering the metal from solution...

Jan 1, 1967

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

By Keet B. A, Waid J. S

The Gippsland Basin is one of Australia's most important producers of petroleum products. An inevitable byproduct of the production, refinement and transport of the millions of barrels of oil is thousands of tonnes of waste. These wastes are generated from the wellhead through to the petrol bowser and range from oily brines and coal tars to oil and petrol contaminated soils. The vast majority of these wastes are of a relatively low toxicity and most importantly are carbon-based and biodegradable. Current disposal practices tend to ignore the latter characteristic and inappropriate and/or expensive waste disposal solutions such as landfilling (tipping), incineration or ocean outfalls are the result. A very cost effective and environmentally friendly alternative is land treatment of such wastes. Landfarming, as it is called, has been successfully practiced in Europe for over a decade. Essential features of the system are: ò Application of a predetermined quantity of biodegradable waste in liquid, sludge or highly contaminated soil form, to pre-ploughed soil with concurrent addition of nutrients (N, P and trace elements) and lime to encourage bacterial activity. ò Harmless bacteria already present within the soil break down the carbon-based compounds into carbon dioxide, water and waste heat, WHILE concurrently generating new cells. The breakdown occurs over a period of weeks to months and continues with time with the extremely low levels of the more difficult waste types being the last to disappear. ò Further waste is applied to the soil at regular intervals. The treatment area may be dedicated to landfarming or may be used alternatively for agricultural purposes. Application rates vary but may be as high as 800 tonnes per hectare per year for wastes such as refinery sludges.

Jan 1, 1992

The following observations on the mineral composition of the lead-zinc ores at Captain's Flat, New South Wales, are based upon the examination of a collection of specimens made during a brief visit to the mine in January, 1942, in conjunction with earlier studies of specimens and mill products, which have 'been the subject of various Mineragraphic Reports, Captain's Flat is about 35 miles south of Canberra, and is connected with the main line from Goulburn to Bombala by a branch line to Bungendore, 23 miles away from the mine.The geology of the mine has been described by Kenny and Mulholland2 and by Harper.3 The country consists of Silurian sediments, which have been invaded by a composite sill of quartz-felspar-porphyry. Both sediments and sill have been folded gently, the axial lines of the folds trending north and south. In the vicinity of the orebodies the folds are steeper, and thru,st faults are associated with the anticlines. The intense compression and shearing that accompanied the faulting has converted the adjacent porphyry to schist. The Captain's Flat orebodies occur along such a zone of shearing and faulting, on the eastern limb of a steep, north-pitching anticline. At their southern end the orebodies are enclosed in the slates underlying the porphyry, but the northerly pitch of the fold carries the slate to greater depth in the northern part of the mine, where the orebody lies beween schistose porphyry on the hanging wall and massive porphyry in the footwall.THE OREBODIESThe orebodies occur along a N.-S. strike length of 4,200 ft., and from the point of view of mining, fall into three sections: the Elliot's Section to the north, the Central Section, and the Keating's Section to the south. The Keating's Section is separated from the Central Section by 500-600 ft. of mineralised ground of so low a grade as' to be called barren, and is offset about 125 ft. to the 'east of the Central body by an oblique fault striking N.300E. Elliot's Section and the Central Section are connected by persistent veins and stringers of lead-zinc ore, but although these are...

Jan 1, 1943

The increased cost of imported oil fuels, coupled with our understandable reluctance to commit ourselves to the use of nuclear energy, has resulted in a renewed reliance on coal as a primary source of energy. New Zealand is fortunate in being fairly well endowed in its coal resources, but their exploitation until now, has been on a relatively small scale. Future exploitation, whether from underground or open cast mines, must be on a very much larger scale. This paper outlines some of the factors which should be considered in planning large open cast mines.

Jan 1, 1976

The theme of this conference is æRediscover OtagoÆ. In order to ensure the development and exploitation of mineral discoveries in New Zealand, considerable capital will be required, particularly from overseas. This paper briefly reviews the Government's foreign investment policies and procedures and highlights some trends.

Jan 1, 1992

By W T. Yen

Pyrrhotite crystallises as either a hexagonal or monoclinic structure, both of which can occur in ore deposits. In general, pyrrhotite is not considered as a valuable mineral unless it contains considerable amounts of other metals like nickel or copper. In fact it causes numerous problems in flotation including intensive oxygen consumption, which results in poor selectivity among sulphide minerals in the processing of complex sulphide ores. Also, because of its high sulphur content, pyrrhotite is a major contributor to environmentally detrimental sulphur dioxide (SO2) emissions from smelters. Pyrrhotite also interacts galvanically with grinding media via electrolyte species present in the flotation pulp, resulting in media corrosion. The most effective way to reject pyrrhotite is through a separation stage, which may be difficult when both types of pyrrhotite are present in the ore. In this regard depression of pyrrhotite through a flotation stage may be applied. Pyrrhotite depression by either intensive oxidation or by using sodium cyanide has been practiced. Results present in this work show that NaCN can depress pyrrhotite effectively when combined with an alkaline environment and low collector concentrations.

Jan 1, 2002

By L Forrester

The tube bundle system is an integral part of an underground coalmine’s gas monitoring system. The maintenance of these systems is vital to ensure the quality of the data produced. Integrity testing of the tube bundle lines is required monthly, as specified in Standards Australia AS/NZ 2290.3 (1990). The various forms of integrity testing are reviewed, including pressure testing and introduction of a known gas. This paper provides a recommended and standardised methodology for those techniques where none currently exists. A strengths, weaknesses, opportunities, threats (SWOT) analysis is performed. The parameters considered for the SWOT analysis include resourcing required by the mines, time for the testing to be performed, and quality of the results produced. The suitability of such integrity testing protocols to be used in a mine emergency situation is also evaluated.CITATION:Forrester, L, 2017. Tube bundle integrity testing methodologies, in Proceedings Australian Mine Vent Conference 2017, pp 129–136 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017