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Utah Development Company operates a mine at Blackwater with a present annual production of 4 000 000 tonnes of coking coal. Mineable seams outcropping on the company's lease are part of the Permian Mammoth Rangal Coal Measures. Current operations are based pre- dominantly on the Main Lower seam. Coal quality variations occur along the seam strike, in the direction of seam dip, within the seam plies and in isolated anomalous areas. Raw coal of non-specification quality is washed to reduce ash and sulphur and to improve the free swelling index. Raw coal meeting specification quality is sent directly to product, by-passing the washplant. Careful attention to mining, coal preparation and product blending is necessary to ensure that the combined product meets specifications.

Jan 1, 1974

Many of the recent major achievements of our industry were visions of our forefathers in the 1800s. Only recently has technology been able to meet the vision of our predecessors. This paper follows the development of selected aspects of tunnelling from the 1800s to present day. It appears that, at the turn of the century, technology is beginning to catch up with our vision and we are able to put our ideas to work more quickly.

Jan 1, 1999

Roadheader tunnelling machines have been used in Australia by both mining companies and contractors involved in the mining and con- struction industries since the early 1970's. They have both advantages and limitations, and this paper discusses machine excavation from the point of view of a contractor who has both reaped the benefits and suffered the conse- quences of using roadheaders. The paper also includes brief descriptions of three projects tackled by roadheader, all the projects being Declines.

Jan 1, 1987

By Beavis FC, Box JC

The important chemical and fluid flow phenomena in heap, dump and in situ leaching are summarised. Published, quantitative models of these processes are critically reviewed, and their potential applications outlined. Comparison between the independent predictions of one of the models and column leach test data reported by others confirms the potential. Some recent developments by the authors in the fields of fluid flow through unbroken ore and modelling of the more complex chemical systems are briefly Described.

Jan 1, 1981

The Golden Pig Mine is wholly owned by Bunnine Operations Limited and is located in the Yilgam Goldfields at Southern Cross, Western AustraliaThe paper briefly describes the geology and history of the operations. Mining is by shrink stoping, both hand held and mechanised. Advantages and disadvantages costs of the mining system are discussed.

Jan 1, 1993

By T Raynlyn, J J. Campbell, J M. Young

In order to correctly predict the performance of beneficiation processes, such as hydrocycloning or ultrasonic treatment of iron ore fines, it is important to understand possible changes in size distribution, mineral composition and textural peculiarities. During beneficiation processes, iron ore can be subjected to various physical actions which may result in changes in size distribution. In the case of soft or friable ores, attritioning and/or deagglomeration may have a significant effect on both separation performance and product stream specifications. Optical image analysis tools, which give statistical information on a particle by particle basis, can help in better understanding the response of the ores to these processes. An experimental study has been conducted to investigate the response of a haematitic-goethitic iron ore to a combination of stirring and ultrasonic treatment. The effect of stirring and ultrasonic treatment on the size and mineral distribution has been quantified using image analysis and automatic ore texture classification. This approach has been applied to several size coarse fractions of the initial feed and product. The results show that, following treatment, the mass proportion of ore texture classes which contained higher amounts of ochreous goethite and kaolinite had significantly decreased compared with that in the feed, while the proportion of texture classes where haematite was the major mineral had increased. Liberation analysis also showed a significant increase in the proportion of particles with more than 95 per cent haematite and vitreous goethite.

Jan 1, 2007

By Jensen W. S

The Mount Morgan ore-body is intersected by dykes to such an extent that it presents peculiarly difficult problems in extracting ore. These are shown on Plates Nos. LXVII. and LXVIII. Besides ,these dykes there are innumerable "heads," which alsoare a source of danger. Falls of ore occurred in the end of the year 1908, resulting in serious loss of life to miners employed. It was decided, after an exhaustive inquiry, to change the entire system of mining from the" flat backed stope system" to the" square set sectional system ," the latter being more flexible and allowing bad ground to be cut out from a safe position; but it became evident that, whatever system was adopted, there would be more or less danger unless all the dykesand heads known were picked up, and their continuation plotted on a special set of plans on which the general scheme of stoping could be plotted from time to time as work progressed. It is worth while pointing out that, in every other branch of engineering, it is usual to design the work, and that only in mining engineering has it been common to do the work first and plot it down afterwards.The term "sectional analysis" is familiar in most branches of engineering design, and as applied in this paper to mining, may not bear the same meaning, but the general purpose is analagous, and there is no other term used.

Jan 1, 1911

Pisolitic iron ores (also known as channel iron deposits) are an important resource of medium-grade iron ore in the Hamersley Province of Western Australia. They are a special case of transported pisolitic ferricrust, differing from normal transported ferricrust only in the exceptionally high iron and low alumina content. The pisoids typically range up to 5 mm in diameter with abundant particles of ferruginised fossil wood up to 15 mm in maximum diameter preserved in the sediment. Field observations indicate that pisoliths are commonly initiated by the action of raindrops on iron-rich soil. Pisolites form by the impact of raindrops forming coated beads of ferruginous soil, which after dehydration obtain additional coatings during successive showers. Thick deposits of pisolite that are transported and deposited primarily by sheetwash form in the distal regions of the pediment. A size range limited to particles that may be transported by extremely shallow water characterises the abundant fossil wood fragments. The absence of fine sedimentary layering in pisolitic iron ores is explained by the action of soil-forming processes after deposition, while the major coarse bedding features derive from successive erosional and depositional events in the evolution of the pediment. They are not deposited in channels by rivers which, in arid to semi-arid conditions, typically deposit quartz sands and gravels with characteristic point bars and current bedding, abundant ferruginous granules, but rarely pisoids. However, they may fill abandoned river channels.

Jan 1, 2007

The Teutonic Bore deposit lies in a major greenstone belt within the Archaean Yilgarn craton of Western Australia. It occurs towards the base of a suite of tholeiitic basalts, some 100 m above a felsic volcanic pile of rhyolitic composition. Sediments comprise a minor, albeit important, percentage of the mine stratigraphy.The deposit consists of a single, steeply dipping lens of massive sulphides totalling 1.4 million tonnes grading 4.16 per cent Cu, 16.4 per cent Zn, 1.22 per cent Pb and 203 g/t Ag. In addition, cross cutting "stringer" mineralisation in the footwall contributes a further 0.75 million tonnes at 2.38 per cent Cu, 1.92 per cent Zn and 52 g/t Ag to the mining reserves. Principal primary sulphides in massive and disseminated mineralisation are sphalerite, pyrite, chalcopyrite and galena, while minor amounts of arsenopyrite and argentiferous tetrahedrite are also present. Weathering has affected the primary mineralogy down to at least 90 m, resulting in a strongly leached oxide profile to about 85 m, overlying a thin, erratic zone of chalcocite supergene enrichment.Lateral metal zoning is marked both in massive sulphide and stringer mineralisation, with Cu/Zn ratios decreasing away from the centre of the orebody. Alteration is well developed in association with footwall stringer mineralisation, changing from a central Fe-Mg carbonate, chlorite and silica alteration zone below the massive sulphides to an outer halo of sericitisation. The spatial distribution of these minerals is patchy. Geochemically, the footwall alteration zone is characterised by central Cao, Na20 and Sr depletion (with less regular enrichment of SiO2 , Fe and MgO), surrounded by a peripheral zone of K20 enrichment.Evidence supports a classic volcanic-exhalative origin, involving submarine discharge on the flanks of a rhyolitic dome and accumulation of the massive sulphides in a local palaeotopographic depression. The sulphides overlie their feeder zone as shown by alteration and stringer mineralisation. Tholeiitic wallrocks are thought to be genetically unrelated to the mineralising solutions, although their presence as a cap over the felsic volcanics may have permitted the build up of a circulating metalliferous brine system prior to sulphide deposition.

Jan 1, 1984

By Ruffles B. R

A computer simulation has been developed to model the flow of copper ore in Isa Mine. It simulates extraction of copper ore from the 1100 orebody by load-haul-dump (LHD) units to ore passes, haulage from chutes on 19 level by Rockflo trains to crusher bins, crushing and hoisting. It can assess in terms of the tonnage and head grade of ore hoisted, the effect of varying operating strategies, as well as measur- ing shortfalls in required capacities of any of the operations (extraction, hauling, crushing and hoisting). The simulation was designed as a modular, deterministic, steady-state model with parameter input allowing complete flexibility in its use. Queuing theory is used extensively to evaluate the effect of interference at potential bottlenecks. The model has been used to determine the effect on production of varying train sizes, maintenance policies on the haulage circuit, orepass capacities, and extraction operations.

Jan 1, 1974

By Gadd D. E

Since October 1972, New Zealand Steel Mining Ltd has loaded around 10 million tonnes of ironsand concentrate from single-point mooring buoys located off-shore at Taharoa on the west coast of the North Island of New Zealand. Before the first off-shore loading system was installed a considerable research effort was applied to proving the slurry loading technique. Subsequently the system has been expanded and a new buoy, pipelines and pumping system were installed in early 1978. Since then 110,000 DWT class ore carriers have been loaded at rates of around 2600 tonnes per hour through twin submarine pipelines. This paper reviews the operation of the shiploading system and attempts to answer the question: "If the Taharoa operation were to be planned in 1980, would the same research spending be necessary or have published research results since, made such practical tests unnecessary?".

Jan 1, 1980

By Das S. C

A detailed study was undertaken on the effect of Fe+3 in combination with LIX64N during copper electrowinning from sulphate electrolytes. The results show that the presence of Fe+3 not only affects the current efficiency during copper electrowinning but also affects the cathode quality. The effect is enhanced by electrolysis parameters like temperature, circulation rate, current density, etc. No significant effect was found from the presence of Fe+2. The presence of Fe+3 along with LIX64N causes a synergistic effect and results in a drastic fall in current efficiency. Moreover, cathode quality is also affected. A pyramidal structure is favoured in the presence of Fe+3 but the presence of LIX64N along with Fe+3 promotes a ridge structure. Addition of thiourea not only causes modification of cathode deposits, but also a rise in current Efficiency.

Jan 1, 1992

A general review of grinding mill steel liner evolutions/developments in recent times. The driving force behind these developments has been the mill operators desire to minimise the nett cost of their operation. These developments have resulted from a team approach between supplier, operators and reline crews. The move towards larger diameter high aspect mills, faster mill speeds, pebble ports and the use of large diameter grinding media has affected the traditional liner designs, which is placing higher demands on the supplier to meet these new working parameters and expectations. Operators are also taking closer ownership in the liners being supplied, as demonstrated by the development of their own mill liner specifications. This paper outlines some of liner developments and changes undergone at various milling operations around Australia and overseas (such as Cadia Hill, Kidston, Ok Tedi Mining, PT Freeport, etc) and where to in the future?

Jan 1, 2000

By F Linares, B De Waele, K Bischoff, M Lacorde, G Loveday

Recent exploration has identified the presence of detrital iron deposits (DIDs) associated with banded iron formation (BIF) units in the north-west of the Congo Craton, Gabon. The regional geology comprises a complex of granitoids and gneisses assigned to the Archaean Chaillu Complex, within which older slivers of lower amphibolite-grade greenstones are preserved including muscovite-biotite-garnet-bearing felsic schist, amphibolite and BIF. These units are typically overlain by several metres of residuum comprising colluvium, eluvium and duricrust. The residuum is overlain by a regionally extensive loess cover from 2 m to 10 m thick.The DIDs occur within the weathered residuum as mostly unconsolidated gravels with lesser canga (CAN) duricrust draped over deeply weathered hematite. Head grades are in the range of 45 to 52 per cent Fe. Fresh BIF, located from 30 to 50 m below surface, is comprised of magnetite-quartz±amphibole. The detrital iron gravels are comprised of rod- and plate-shaped clasts of hematite (martite)-maghemite-goethite composition, in a ferruginous sand to clay-sized matrix. The DID form ridges and plateaus that coincide with magnetic highs defined using high-resolution ground magnetic surveys.The field relations and petrography indicate that the detrital iron accumulations are the result of weathering (including enrichment) and erosion of primary BIF. This includes removal of quartz, further oxidation and re-cementation of BIF to form ferruginous caprock. This cap and the in situ oxidised BIF were subsequently disaggregated and liberated, and further weathered to form the detrital iron accumulations.Metallurgical test work on bulk detrital iron samples has shown this material can be upgraded to lump and fines iron ore products with grades of 62 to 65 per cent Fe using simple scrubbing and wet screening, followed by dense media separation of the -1 mm fraction, with overall mass yields from 75 to 85 per cent. The test work indicates a high ratio of lump to fines products, sometimes exceeding 50:50.CITATION:De Waele, B, Lacorde, M, Bischoff, K, Loveday, G and Linares, F, 2017. Geological and metallurgical characteristics of banded iron formation associated detrital iron mineralisation in Central West Africa, in Proceedings Iron Ore 2017, pp 259–268 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

During 1979 the writer had the privilege of interviewing about 50 people with varying degrees of involvement in the industrial arena and all of them in one way and another, had a part to play in the huge and intricate saga of Australian employee relations. They fell into the following' categories Industrial Relations Officers/Managers Academics Politicians Union Officials Representatives of Employer Associations Senior Industrialists Commission Members (State and Federal) Sundry (Journalists, Government Officials). This paper seeks to give an account of their views on various aspects of industrial relations. The interviews conducted were all on a personal and confidential basis so it can be expected that sources will not be identified. Suffice it to say that this account represents, albeit in "potted" form, the opinions of some of the most experienced individuals in the country. It will be seen that in most of the vital areas there is a remarkable lack of consensus. It should be noted that this lack of consensus existed within each of the groups mentioned.

Jan 1, 1980

The primary objective of designing, constructing, commissioning and operating a technically and economically viable processing plant cannot be achieved without a rigorous scientific understanding of the chemical principles underlying every facet of the total flowsheet, from feed preparation through to a final product. Having developed a thorough understanding of the chemistry involved, the next challenge is to match the innovative advances with the necessary engineering skills. In simple terms, there is little point in proposing a new processing route if it is not possible or practical to design, construct, commission and operate it. Thus to achieve our objective, it is necessary that processing facilities that are both smarter and cheaper be developed. This presentation highlights a number of the more significant research and development activities that are designed to facilitate the conversion of a smart idea into a real process. Following a brief discussion of several examples, the presentation concludes with the observation that a pro-active team approach is almost mandatory in order to achieve an acceptable outcome.

Jan 1, 2000

This paper reports on the field results of using electronic detonators to improve blast outcomes. OricaÆs electronic detonator, the i-konTM Digital Energy Control System, allows exact and precise timing in 1 ms increments from 0 to 15 000 ms. This gives the blast engineer and shotfirer the ability to fire a blast using any possible desired sequence. In the three years that have followed the release of the i-konTM System, Orica has been re-exploring ways of initiating blasts using the abilities of electronic detonators to improve fragmentation, diggability and crusher throughput. This study began with revisiting fundamental blast theory, lead to generation of new state of the art computer fragmentation modelling and ended with many iterative field trials of i-konTM blasts across a wide selection of mining methods and rock types. At three sites a detailed measurement process was undertaken to compare the results of pyrotechnic blasts with i-konTM blasts. This paper will detail the significant improvements in fragmentation, diggability and crusher throughput that was found at these sites.

Jan 1, 2003

By P D. Williams

The Phoenix mine is one of NewmontÆs open-pit operations located in Nevada. Mining started in 2005, with the mine producing gold, copper and silver. The mine life is about 20 years. The gold grade estimation uses the Newmont in-house indicator kriging approach to handle the high variability in drill hole composite grades and support mining selectivity. Each block contains up to 200 subblocks with different gold grades. A flotation mill is designed to process oxide and sulfide ores, recovering gold, copper, and silver. An additional copper leach process is currently under study to process low gold and high copper oxide material with low copper recovery in the mill. The metallurgical recoveries and processing costs are dependent on many variables including rock formation, metallurgical domain, cyanide soluble copper and sulfide contents. This paper describes the Newmont in-house indicator kriging procedures and the revenue based mine planning software system implemented at Phoenix mine to address the complexity resulting from multi-process, multi-metal and indicator kriging model.

Jan 1, 2007

With the recent increase in the number of underground secondary sulphide dust explosions in Canada, Australia and elsewhere in massive sulphide ore mining industry, establishment of quantitative and realistic methods of analyzing the mine dust is of paramount importance. This paper examines and analyses dust samples from a mine area that has very recently experienced sulphide dust explosions. Also, it attempts to evaluate the physical and chemical characteristics of the dust. Explosibility of the dust samples was determined by quantifying the oxidation reaction of the sulphide dust particles in a 1.2 L, Lindenberg open horizontal tube furnace. Percentage sulphur', % S oxidised during ignition of a dust sample of known assay, % S and dust concentration (g/m3) were determined by the quantitative chemical analysis of SO2 gas produced during the oxidation reaction. A dust sample with high sulphur content, 22.3% S (assayed) and mean particle size 9.82 pm, was found to exhibit a low degree of oxidation compared with a sample of low sulphur content, 15.44% S and mean particle size 21.7 tcm, at the same Temperature.

Jan 1, 1988

By Bof J, Lowe S

BHP's newest colliery on the Southern Coalfield Is Tower Colliery. It is situated near Wilton some 60 kms south west from Sydney. It commenced its operations in 1978 and since that time has experienced considerable roof problems. In its eight years of operations, production has been 936 687 tonnes to December 1985. To a certain extent this is a reflection of the ground control r,,b1cros present in the colliery. paper out Iines the signif mt g,, logical features that are known to exist in the colliery and their influence on roadway development. Faulting has hindered the mine's development and an igneous intrusion has had outhursting associated with it. The prevailing roof rock has also had an impact on the roadway conditions. The paper will look at intersection deformation in present workings. Extensometers have been installed in these areas and provide measurements to verify visual observations. The results show a significant increase in roof movement as the roadway is developed from a single heading, to a T-intersection and then Into a four-way intersection.

Jan 1, 1986