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The development of the Moura Coal Preparation Plant is described, commencing with the first'stage of the plant commissioned in 1963. The subsequent expansion stages are traced through to October, 1973. The plant has undergone frequent stages of expansion and modification and this process is continuing. The development programme for 1974 is described as proposed in late 1973. The characteristics of the Moura and Kianga field coal seams with respect to washability are summarised and some comment is made on the blending of these coals prior to washing, to ensure production of export grade coal within specification.

Jan 1, 1974

This paper summarises the influence of slurry rheology on the grinding throughput of batch laboratory and continuous plant-scale mills operating in open and closed circuit configurations. The results of controlled changes in percent solids, particle size, slurry temperature, and viscosity control chemicals are demonstrated. An underlying rheological explanation of the above factors is offered which involves tying the specific rates of breakage that are occurring in the mill with the specific rheological character that the slurry is exhibiting at any given set of operating conditions. Some industrial scale operating guidelines are presented which have proven useful in increasing the net pro- duction capability of grinding circuits.

Jan 1, 1978

By Y Xie, L O’Connor, S C. Dominy

"Sheeted vein gold deposits are characterised by multiple subparallel veins and free milling gold. In situ heterogeneity of mineralisation results in grade and process parameter variability, which will increase project risk. Measured variability is often enhanced by poorly designed sampling and test work protocols. Protocols that are optimised within the framework of the theory of sampling to suit the ore type, together with quality assurance/quality control systems, will reduce variability and provide fit-for-purpose results. The geometallurgical approach requires spatially distributed samples within a deposit to support variability modelling. Diverse attributes from core logging, mineralogical/textural determination and small-scale tests are used to measure variability. This contribution emphasises early stage geometallurgical intervention during project development. It presents a discussion of representative sampling in the context of the theory of sampling. A case study presents a protocol that exemplifies how data can be gained from a well-designed and planned program to support a resource estimate and prefeasibility study.CITATION:Dominy, S C, O’Connor, L and Xie, Y, 2016. Sampling and Test Work Protocol Development for Geometallurgical Characterisation of a Sheeted Vein Gold Deposit, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 97–112 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By N Lima, A Piçarra, L Filippov, I Filippova, M Marques, K Silva

The iron industry produces a considerable amount of tailings per annum, due to its substantial volumes of production. The actual iron ore processing routes require the removal of slimes fractions. In addition to iron oxides and quartz, the iron ore slimes are generally composed of other minerals such as kaolinite and finely dispersed iron hydroxides which impact significantly the performance of reverse cationic flotation. In this study, we propose a two stage processing route that would allow further beneficiation of iron slimes which are not successfully beneficiated, avoiding their disposal as waste. The new amidoamine reagent was tested as a collector in a two-stage route to process two samples of iron ore slimes with d50 close to 10 μm and with high kaolinite content (13 to 20 per cent). The results showed that it was possible to obtain iron concentrate with 66.5 per cent iron and 48.4 per cent mass recovery for a feed containing 48.9 per cent Fe associated with hematite (39 per cent) and goethite (32 per cent). The collector efficiency was improved by mixing with frother for the slimes with higher goethite content of 55 per cent: the concentrate grade was increased from 58.8 per cent to 64.5 per cent with addition of the frother at the expense of reducing operation metallurgical recovery from 87.8 per cent to 75.6 per cent. The efficiency of the process was improved by applying an external energy impact to disperse the fine particles and clean the surface of the minerals. The new amidoamine collector does not require a depressor such as corn starch and may provide the development of new concentration routes for complex ultrafine iron ores. The combination of the amidoamine-based flotation at first stage with high intensity magnetic separation allowed development of optimised two-stage processing routes to valorise the iron ore slimes rejected to the tailings in the actual flotation plant.

Sep 18, 2023

By Mikula PA

This paper presents the results of in-situ and laboratory investigations into a mining method which utilises conventional continuous mining techniques to carry out two passes in thick coal seams, resulting in the development of stable pillars with relatively small width dimensions and heights up to 6 m. Geotechnical investigations included structural mapping, brightness logging and standard laboratory testing. Virgin stress was measured using overcoring techniques. Two approaches to pillar design were used in the study. These were; pillar design based on empirical formulae and laboratory testing, and pillar disign using calibrated mathematical models. A trial panel was developed at 300 m depth to study pillar deformation and stress changes due to mining. The extent of rib deformation was studied using borescopes and extensometers. In-situ geotechnical measurements were used to calibrate displacement discontinuity and finite element mathematical models of the coal seam. These models were then used to predict the behaviour of a small panel of pillars which were to be developed to 6 m height. The mining method was shown to be feasible provided adequate rib support was installed. The benefit of rib support was found to be two-fold, in that it increased confinement of the pillar in zones of low horizontal stress, while reducing horizontal stress relaxation in zones of high horizontal virgin stress. The possiblity of roof control by designing the small pillars to yield on retreat is discussed.

Jan 1, 1986

By Stevens P

The Isa Mine of Mount Isa Mines Limited currently produces 5.4 million tonnes of copper ore and 3.3 million tonnes of silver, lead and zinc ore annually. Of this, 5.1 million tonnes of copper ore and 2.2 million tonnes of silver-lead-zinc ore is produced by sublevel open stoping. This paper summarises the capabilities, operating practices and problems encountered with current production drilling practices used to drill sublevel open stopes at Mount Isa.

Jan 1, 1982

The coal resources of the Singleton- Muswellbrook area of New South Wales are of major importance to Australia, and are likely to play a significant role in meeting the expanding demands for energy in many countries of the world. Coal resources of 45 thousand million tonnes of which 15 thousand million tonnes lie at a depth of less than 200m have been estimated. The history of coal mining in the area commenced in the mid 1800's and has been one of fluctuations in production but of rapid expansion in more recent years. It is destined to become the largest coal producing area in New South Wales. Coal is being won from the area by strip mining, open pit mining and by underground means. The techniques involved are described. The area is well endowed with infra- structure such as modern towns, railways, road- ways and access to port facilities. Production of both coking coal and steaming coal is expected to rise significantly within the next 25 years. A large proportion of the State's anticipated increased production to between 117 and 177 million tonnes by the year 2000 is likely to come from this area.

Jan 1, 1979

By Larkings RH

The high gas emissions associated with the depth of mining and very high coal extraction at some Australian Collieries have provided a need to investigate the influence of geological and mining conditions on levels of gassiness. The introduction of longwall extraction in particular is associated with complex strata control problems and quick changes in gassiness. To this stage of Australian coal mining, no standard method has been developed to predict the different levels of gassiness associated with the various geological and mining conditions; and the relationship between coal output and total methane make has not been established. For local conditions, with a large number of coal seams lying in close proximity to the working seam, the significant contribution of gas emissions from adjacent strata was expected, especially as strata relaxation occurred during longwall mining. This depends mainly on geological conditions, strata control and coal production. For the deepest of the B.H.P. Collieries in the Newcastle region, the relationship between coal output and total methane make has been investigated by systematic gas balance measurement during longwall extraction. The computer method of iteration was used to approximate the mathematical equation from the initial graphs of coal production versus quantity of methane in the ventilation system for various strata conditions. The angle of caving was established for local geological and mining conditions, for planning and design of the positions of cross measure boreholes.

Jan 1, 1986

The Lake Rotokaua sulphur deposit, near Taupo, New Zealand, is a lacustrine sedimentary ore body, 220 acres in area and from 7 ft to 96 ft thick, containing, within the area drilled to date, some 20 million long tons of ore averaging 25% elemental sulphur in unconsolidated tuffaceous diatomaceous clay, overlain by about 120 ft of pumice sand and by the shallow Lake Rotokaua. An additional amount of perhaps 4 million tons of sulphur is regarded as probable in the area remaining to be drilled. Current economic studies cover the problems of mining an unconsolidated water-saturated formation with some residual thermal activity nearby; conservation and restoration after mining in a scenic recreation area; beneficiation of the ore and extraction of high- purity sulphur, principally for fertilizer manufacture. The deposit has additional importance as a pointer to possible further discoveries in the Thermal Region.\

Jan 1, 1971

The Porphyry Gold Mine (150km NE of Kalgoorlie) was reopened in November 1983 with production commencing in April 1984. Original reserves quoted for the open pit were 822000 tonnes at 5.2 g/t Au based on wide spaced diamond drill holes. Close spaced grade control drilling has revealed some loss of tonnage and a significantly lower grade. In the area of the pit mined to 30 June 1985 this grade control reserve estimate contained 67% of the gold in the original ore reserve with the grade being 19% lower. It is anticipated that the final grade control reserve estimate will contain around 80-85% of the gold contained in the original reserve. There has been close agreement between the Mill Head grade (4.19 g/t Au) and the grade control predicted grade (4.2 g/t Au) confirming that dilution is not a major problem. After initial poor agreement (attributed to "lock-up" in the circuit) the bullion calculated head grade steadied out at 93% of the grade control prediction. This difference is considered to represent the geostatistical bias in the drill hole/crushed rock sampling. Gold recovery has been in the range 93-95% (compared with bullion calculated grade). The net result is that the recovered grade of ore mined to 30 June 1985 is 70% of the original ore reserve grade.

Jan 1, 1986

Any future developer of underground mining on the Bendigo goldfield will need to understand the unique geology and gold occurrence of this field. The development and sloping system employed will be primarily designed around these unique features. Modern techniques and equipment used in narrow vein mining will be applicable in this situation.The purpose of this paper is to examine the important geological features of the field as well as the known historical occurrences of the type of gold deposition in the ore bodies. This information will point to a system of development and extraction which will accommodate these features.

Jan 1, 1993

The Research Centres Program initiated by the Federal Government and supported by the mining industry has had a major impact on geoscience research and education during the past five years. Eight major university based-Geoscience Research Centres are currently supported by the Government, including four Key Centres of Teaching and Research and a further four Cooperative Research Centres (CRCs). The Research Centres Program has led to a concentration of high quality research and teaching in areas of demand and strategic importance creating strong university - industry linkages and a source of well trained and motivated graduates. Over the last decade Australia's reputation as a leader in mineral exploration and ore deposit research has grown substantially, in part because of the development of the Research Centres Program, and to increased collaboration and interaction between research groups and exploration geoscientists across the industry. During a period when ore deposit research activity has been decreasing in other countries (eg USA, Canada, Japan and most European countries), equivalent research activities in Australia have been increasing, within a well co-ordinated national framework. The future challenge for universities and the mining industry will be to maintain the momentum of the successful research centres in order for the centres to become self-funding over a six- to nine-year period.

Jan 1, 1996

An approach to underground mining of shallow dipping, thick seam coal is proposed in broad outline. The method is based upon overhand slice and fill, with hydraulically emplaced washery refuse as the filling material. Likely fill behaviour and character- istics are discussed and likely problem/investigational/ research areas defined.

Jan 1, 1976

The Mount Morgan eopper-gold orebody is contained within a series of Mid-Devonian volcanics which occurs as a roof pendant within Permian granite. The ore minerals comprise pyrite, chalcopyrite, and local aggregations of magnetite and pyrrhotite. Silver-rich gold (electrum) is disseminated through the ore usually in ultrafine to sub-microscopic dimensions. Accessory minerals include marcasite, digenite, chalcocite, covellite, sphalerite, bismuthinite, molybdenite, calaverite, petzite, and cassiterite.Very minor accessories include cubanite, tetrahedrite, galena, arsenopyrite, hematiIe, goethite, and rutile. The gangue minerals are quartz, predominantly, with minor amounts of chlorite and sericite.Study of microtextures of a representative suite of specimens from Mount Morgan does not reveal any criteria indicative of metasomatic replacement but does show, in the case of pyrite, evidence strongly suggestive of annealing recrystallization. Other textures in pyrite indicate porphyroblastic growth of the iron sulphide.It is inferred that the Mount Morgan orebody is genetically related to the volcanic rocks and was later contact metamorphosed by the intrusive granite or by the series of intermediate to basic dykes that transect inmine area. On this basis the Mount Morgan orebody would be a contact metamorphosed volcanic hydrothermal deposit emplaced, according to recent studies, along a pipe-like zone of brecciation.

Jan 1, 1967

The development of present methods of pillar extraction has evolved from the very earliest of hand mining operations which were limited in scope by venti- lation and transport considerations. Conservation and safety considerations also have led to the current shortwall operations with conventional equipment and powered supports. The shortwall methods have had significant effects on safety, costs, con- servation, flexibility, and other aspects of pillar extraction. The present stage falls short of the ideal but is some guide to prediction in what direction may lie the ideal methods for the future.

Jan 1, 1974

By M Medina, J Alexander, R J. Longey

Capricorn Copper Pty Ltd (CCPL) are operating the Capricorn Copper Mine located at Gunpowder, Queensland. As current holder of the environmental authority for the site, CCPL have obligations to rehabilitate areas of the mine that are no longer operational and have the potential to cause/contribute to environmental harm. CCPL sought a voluntary Transitional Environmental Program (TEP) to provide an agreed program of works to cap and rehabilitate the former Mammoth Tailings Storage Facility. The voluntary TEP contained conditions that were required to be met, to reduce the potential for environmental harm from the facility. The former Mammoth Tailings Storage Facility commenced use in the early 1970’s, and is an unlined valley in-fill structure, contemporary in design compared with other such approved structures of the era. The decommissioned Mammoth Tailings Storage Facility, now known as the Old Tailings Storage Facility (Old TSF), has been a legacy source of contamination due to the existing capping not meeting modern cover criterion, and allowing oxidisation and infiltration to the underlying acid forming tailings resulting in Acid and Metalliferous Drainage (AMD) from the facility. A cover design for the Old TSF, and other mine waste storages onsite that required clay capping, had been proposed by previous operators. Under the TEP cover design phase, it was identified that a key constraint was the lack of significant quantities of low permeability clay onsite. The lack of available clay prompted the consideration of alternate lining materials for the Old TSF, with a Bituminous Geomembrane Liner (BGM) being adopted as the preferred alternative. The BGM compared favourably with clay-based materials on seepage analysis, and led to other benefits by eliminating the need for borrowing clay off site, reducing the site’s environmental footprint, and reducing construction time. The BGM cover system on the Old TSF is being monitored with the intent to use this as a case study to confirm expected performance, enabling the cover design to potentially be adopted on the remainder of the site’s mine waste storages that require capping.

Jul 1, 2021

By B Olsson, C Glassock

Computer simulation modelling (discrete event) has been used at Olympic Dam (OD) to model the handling of ore from the point of extraction at the stope drawpoint through to the ore stockpile on the surface. Computer simulation is a well accepted tool for modelling the behaviour of such large and complex operating systems. It is a particularly useful technique in complex operations where there are multiple interactions between the inputs and outputs of various unit operations. In this instance it can be utilised during the early stages of a project, for example, as part of the business case definition phase or the early engineering phase. A well constructed and tested simulation model provides a sound base upon which informed business decisions can be made. Furthermore, the behaviour of the model with varying inputs can help build a solid understanding of how the asset behaves when varying inputs and constraints are imposed upon it and, as a result, the major points of leverage that designers and operations personnel have to affect the real world behaviour of those assets. Better decisions can be made when the right facts can be examined, various options explored and conclusions tested. Simulation modelling is one of the tools available to make this process work.

Jan 1, 2005

Tourmaline-bearing rocks are a rare rock type of Suites 3, 4 and 5 at Broken Hill. Minor laminated plagioclase-quartz-tourmaline rocks occur in association with the quartz- magnetite rocks of Suite 3 with the greatest abundance of tourmaline-bearing rocks present in Suite 4 intimately associated with lode horizon, scheelite mineralisation and zinc mineralistion - all approximate strike equivalents of the Broken Hill Pb-Zn-Ag deposit. Bedded quartz-tourmaline rocks, tourmalinites, tourmaline-rich pelite and tourmaline-bearing lode horizon have been recorded from suite 4. The bedded tourmaline rocks rarely display cross bedding, graded bedding, slump structures and small scale intraformational breccias. Minor tourmaline-gahnite-bearing pelites are present in Suite 5. The sedimentary structures, metamorphic textures, the stratigraphic position of the tourmaline-rocks and the presence of quartz-tourmaline-gahnite-spessartine (-fluorapatite) lode rocks indicates that the mineralisation at Broken Hill and the tourmaline-rich rocks are all products of submarine exhalative hot spring systems which were most active during deposition of Suite 4 rocks. Tourmaline is chemically different from that associated with granitic activity and from other submarine exhalative tourmaline-rich rocks because the premetamorphic alteration at Broken Hill involved addition of Fe, Ti and F and subtraction of Mg - a feature reflected in the chemistry of tourmaline from Broken Hill.

Jan 1, 1983

By Boontanjai C, Boyapati ER

Reagents used for batch flotation tests were Aeroxanthate-343 & 350, Dow Z-6, & reagent-4037 (from Benambra) as copper collectors; Na2SiO3 & Na2S2O3as gangue depressants; lime & HCl as pH regulators; and pine oil & MIBC (methyl isobutyl carbinol) as flotation frothers. A Denver Sub A flotation cell of capacity 250 gms was used for the batch flotation experiments. Atomic absorption spectrophotometer was used for copper assays and microscopy for selectivity and liberation studies. Melbourne tap water was used throughout the experiments. Unless otherwise stated, the following parameters apply to the flotation experiments: flotation impeller speed - 1300 rpm, pulp density during flotation- 22%, reagents addition - in 4 stages, total conditioning time for collectors - 8 minutes, total flotation time- 9 minutes. A variable quantity of copper mineral collector according to the test in question was added, then conditioned the pulp for 2 minutes. The froth was removed by hand, scraping the full length of the cell at constant depth every 10 seconds. No frother is required for this copper tailing flotation. Four concentrates were collected after addition of collector and conditioning at 2,4,6 and 9 minutes. The pulp volume was maintained at a constant level to yield a constant froth depth.

Jan 1, 1990

Gold mineralisation was first noted in 1983 at the Wapolu Point area of Fergusson Island, Papua New Guinea (PNG) during a follow-up regional reconnaissance program. Subsequent exploration programs through to late 1987 completed 22,147m of costean trench sampling, 553 aircore/RC/diamond core drill holes (16,970.5m total) and metallurgical testwork, predominantly on the Wapolu grid in two mineralised areas.Subsequently in 1988, geostat-istical global and polygonal resources were calculated for the main mineral-ised zones, Didigayagaya and Dagwalala. In 1992, a 'probable total reserve' of 1.9Mf @ 2.4g/t with a 1.2g/t cut-off was calculated for these prospects.

Jan 1, 1994