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Maximising margins in today's competitive international commodity markets demands superior productivity. This requires more than simply selecting the best equipment. It requires efficient production and commercial processes together with management systems recognised as international best practice. This paper introduces an integrated way of working that includes management systems for successfully changing work practices and attitudes, developing managers and increasing accountability. It provides an improvement methodology that includes systematic involvement of people in true continuous improvement of processes for maximising productivity and safety while minimising costs. Even though the principles are proven in all industry sectors worldwide, they are not always used correctly. This paper provides examples of traditional performance measurement systems to show how managers miss opportunities to control and improve both production and supporting service processes. It also describes the basic methodology for correct use of the principles and provides examples of correct implementation of modem systems in mining. The charts from actual mining case studies will be elaborated upon in the conference presentation. This paper's main aim is to provide background material for the presentation by introducing integrated principles for building best practice management systems for superior productivity and safety - for higher margins.

Jan 1, 1996

By McKenzie P

The techniques of geological control developed by the Coal Geology Sections of the Broken Hill Proprietary Company Limited and Australian Iron and Steel Proprietary Limited in providing geological service in the coilieries operated by these associated companies cover the provision of geological control for both planning and production in each of which the significance of geology has in the past been only poorly appreciated by the coal mining industry.While the adoption of similar techniques is well within the capacity of major companies there is considerable scope for the development of government geological services providing specialized assistance of this nature for smaller scale producers.INTRODUCTIONThe coal mining industry in Australia can instance many notable mistakes caused by failure to obtain sufficient geological information or by incorrect interpretation of available geological evidence both before the commencement of mining and during the progress of operations. Substantial development undertaken in, areas with insufficient or inferior coal reserves, difficult mining conditions caused by failure to adjust operations to geological circumstances, and the irregular development of mine workings caused by unexpected geological features, all bear witness to the lack of geological foresight by the industry.Along with the more widespread general use of applied geology, an increasing acceptance has developed during the past ten years of the valuable contribution which can be made by this science to the exploitation of coalfields. In spite of the advances which have been made, there is still a wide scope for further detailed application of geology throughout the coal mining industry in Australia.

Jan 1, 1963

This paper considers three aspects of cemented fill practice and research in Mount Isa. Firstly, an account is given of the use of Portland cemented hydraulic fill, considering mainly the role and specifications of the fill used but including û brief description of fill preparation and placement. Data resulting from a Portland cemented hydraulic fill sampling, curing and testing campaign covering about 18 months of operating practice are presented, analysed and discussed. These yield information indicating the mode of operation of a fully-automated fill preparation station, as well as a means of comparing field and laboratory strength results. A technique with potential for use as a fill quality control without actual strength testing is also described. Results of a fill research program conducted by the author in Mount Isa since early 1968 are presented, involving both Portland cemented hydraulic fill and alternative, cheaper, additives for cementing hydraulic fill.

Jan 1, 1971

By R L. Brathwaite

The mesothermal quartz-scheelite lodes of the Wakamarina valley are one of twelve known mined or prospected gold-bearing areas in the Marlborough Schist. Recorded production was 556 kg gold, a little silver, and c. 390 t scheelite. 134 m of the 1800 m long Golden Bar reef are accessible in the No 2 level of the Golden Bar mine. The reef is a typical multi-banded mesothermal vein, mostly c. 1.75 m wide, enclosing narrow horses of schist country rock. Scheelite is sparsely distributed, and is more common in small veinlets in the hanging wall schist. The country rocks are textural zone I-1m schists of prehnite-pumpellyite to pumpellyite-actinolite metamorphic facies. Their geochemistry suggests they are part of the Caples Terrane, and of calc-alkaline volcanogenic arc origin. The associated Wakamarina Quartzite is strongly recumbent folded, and of the same metamorphic grade, with abundant pumpellyite, stilpnomelane, and garnet, presumably spessartine. Although it has geochemical signatures of a deep sea sediment, it is depleted in Cr and Cu, and greatly enhanced in K and Ti, when compared with a standard chert. It also has trace element characteristics of a calc-alkaline arc-related sediment. However, associated greenschist has MORB-like incompatible element chemistry. The Golden Bar reef lies within a steeply dipping, normal to transtensional dip-slip fault adjacent to a shallow-dipping mylonite shear zone, which, at least on the footwall side, is 040 m wide. The shear foliation has been severely dragged down to nearly parallel the Golden Bar reef within 1 m of the quartz lode. Preliminary structural analysis suggests that the shear zone is extensional. X-ray diffraction analyses of the wall rocks show a progressive depletion of amphibole, stilpnomelane, and pumpellyite towards the reef, and enhanced illite/muscovite and Kfeldspar adjacent to the lode, along with possible graphitic carbon within 10m. Two zones of intense quartz veining occur, one adjacent to the hanging wall for 12 m and one from 40 m outwards. Quartz vein systems in the country rock are complex and span from pre-schistosity to post-mylonite. They include multiple generations of quartz, actinolite, stilpnomelane, pumpellyite, albite, adularia, chlorites, illite/muscovite, calcite, and scheelite. Metal analyses across the Golden Bar reef showed gold values of 0.13.1 ppm, and low tungsten values, consistent with the observed sporadic scheelite occurrences. As and Sb are at background levels, but enhanced Cr (150 - 430 ppm) relative to the schists (30 - 41 ppm) suggests that the source hydrothermal fluids passed through and leached mafic to ultramafic rocks.

Jan 1, 1994

The large increase in secondary industries in this country, during the war and post war periods, has caused a shortage of capacity for the production of merchant bar.To overcome this shortage, an expansion of rolling mill facilities has been undertaken by the Broken Hill Pty. Co. Ltd. A small, but modern, merchant mill has been erected at Kwinana in Western Australia and a strip and skelp mill is under construction at Newcastle. The latter mill will roll strip and skelp at present being rolled by the Newcastle 10 in. Merchant Mill, enahling this mill to concentrate on merchant bar production.The Kwinana mill was installed to supply the Western Australian market. This state has a small population (approximately 658,000) and is not at present highly industrialised. It was necessary, therefore, to design a mill which would be capable of producing a wide diversity of sections and could be expanded as the demand increased. To begin with capital expenditure had to be kept within reasonable bounds. The design work for this mill, with the exception of a few specialised items of equipment, was carried out at Newcastle.All design work for the Newcastle mill was carried out by the lVIorgan Construction Co. of America. Although initially intended for rolling flat. products, the designers were asked to make the mill as flexible as possible, so that should the market for flat products decrease, this mill with additional equipment could undertake the rolling of medium sized sections.

Jan 1, 1957

There are circumstances where the ordinary techniques of experimental variography in geostatistics û now in common use despite their recent origin û are not quite successful. This paper describes a new addition to the geostatisticians tool kit developed by one of the renowned leaders in the field to cope specifically with these circumstances. Possible application of this technique will be outlined when it will be seen that there are still problems remaining to be solved in its use for economic evaluation of deposits with irregular mineralisation.

Jan 1, 1984

By A R. Penney

Since mining-induced seismicity first became apparent at the Beaconsfield Gold Mine in 2002, there has been an ongoing program of geotechnical investigations to understand the phenomenon and allow for the development of strategies to manage the risks it posed to personnel, the business and the community at large. Studies resulting from a seismically induced rockfall on Anzac Day 2006 have been extensive, and have advanced the understanding and management of seismicity at the mine. Enhancement of the mineÆs seismic array, implementation of extensive monitoring of ground behaviour, improved ground support and reinforcement design, and ongoing numerical modelling provide a technical framework for the management of seismicity. In addition, extensive involvement of the workforce in risk assessment and the development of standard work procedures (SWPs), has contributed to a æbest practiceÆ approach to manage seismic hazards at the mine.

Jan 1, 2008

The authors describe two stratiform intrusions within a two miles thick ophiolite belt, one of the many ophiolite (serpentine) belts of the eugeosynclinal sequences of the Kalgoorlie System (metamorphic age c.2700 million years). Unusually good evidence of gravitational differentiation involving cumulates for an Alpine type peridotite-gabbro intrusion has been obtained, in spite of modifications of the original igneous rocks imposed by regional metamorphism. Unmetamorphosed relics of cumulate rocks are a surprising feature of this occurIfence.'fhe differentiation process reflected in the layered sequences is compared to that of the Stillwater Intrusion, Montana. Phase, cryptic and rhythmic layering are recognized. The economic significance of this study lies not only in the possibility of nickel mineralization in this ophiolite belt, but also in that much detailed information on the nature of these belts, which is difficult to obtain in the case of the more altered and sheared rocks of the belts carrying gold and nickel ore deposits nearby, is gathered from the Yilmia occurrences.

Jan 1, 1969

By B Powell

Coastal acid sulfate soils (ASS) are wetland soils and unconsolidated sediments that contain iron sulfides which, when exposed to atmospheric oxygen in the presence of water, form sulfuric acid. ASS form in protected low energy environments such as barrier estuaries and coastal lakes and commonly occur in low lying coastal lands as Holocene marine muds and sands. When disturbed, the iron sulfides in these soils can oxidise and produce large volumes of sulfuric acid (essentially similar chemistry to acid rock drainage with mines) resulting in the subsequent release of toxic levels of iron, aluminium, manganese and possibly heavy metals. This results in detrimental effects on aquatic biota, plants, animals and steel/concrete structures and on human health in the surrounding environment. There are an estimated 2.3 million ha of ASS located along 6500 km of the Queensland coastline. In contrast to many mineral sulfides encountered in the mining industry, the pyrite crystals in ASS can be as small as 2 mm and commonly occur as framboids with extremely large surface area per unit mass, substantially increasing their reactivity if exposed to air (oxidation). Highly reactive iron monosulfides can also occur, particularly in drains and shallow lakes. Many coastal areas, where some 80 per cent of the population of Queensland reside, are coming under pressure for agricultural and urban development. Construction of canal estates, marinas, housing/industrial estates, roads, golf courses, aquaculture ponds, sand/gravel extraction and drainage for sugar cane can disturb ASS and release sulfuric acid, which may then drain into adjacent waterways with heavy rain. As development continues to encroach on coastal lowlands, the identification, quantification and management of ASS must be addressed as part of a commitment to the principles of Ecologically Sustainable Development (ESD). ASS can be successfully managed by adopting best practices and following guidelines, but government, community and industry must collaborate to raise awareness, avoid æhot spotsÆ and develop more cost-effective solutions. Scientists led the education and public awareness program showing infrastructure and environmental damages arising from ASS in Queensland. Using results from mapping and research, they convinced policy makers, industry and polititians to accept the need for legislation founded on good science. The resulting æState Planning Policy 2/02: Planning and Managing Development Involving Acid Sulfate SoilsÆ identifies the StateÆs interest in acid sulfate soils. The Queensland Government considers that development involving acid sulfate soils in low-lying coastal areas should be planned and managed to avoid potential adverse effects on the natural and built environment (including infrastructure) and human health. SPP 2/02 states where the policy applies and when a development application will trigger the policy. It can also be used to assist local governments in preparing their planning schemes under the æIntegrated Planning Act 1997Æ. The SPP 2/02 comes with a æState Planning Policy 2/02 GuidelineÆ to provide advice and technical information on interpreting and implementing the SPP 2/02. This guideline has legal status in assisting in the interpretation of SPP 2/02. Those seeking more detailed technical information can now also access the æSoil Management GuidelinesÆ and ASS æSampling GuidelineÆ, available from the Department of Natural Resources and Mines website. These are some of a series of chapters being developed for the æQueensland Acid Sulfate Soil Technical ManualÆ.

Jan 1, 2003

By V Shrotri L Muhmood, P Gandhre

The current work deals with the measurement of some thermophysical properties of Ca(NO3)2 based ternary nitrate molten salts as HTF (heat transfer fluid) / TES (Thermal Energy Storage) material for CSP (Concentrating solar power) plants. The density and viscosity of different compositions of the ternary salt mixture containing Ca(NO3)2, NaNO3 and KNO3 close to the liquidus has been experimentally measured. An attempt has also been made to measure the melting point of the salt using the cooling curve technique as well as Differential Scanning Calorimetry (DSC). Thermogravimetric analysis has also been performed to estimate the peak operating temperature of the salt. Compatibility of suitable pipe material (SS304) with molten salt has also been discussed. The salt mixture proves to be a viable alternative to the already existing HTFs like Therminol VP-1 (organic oil) or Solar Salt® in regards to its lower melting point, wider operating range, low cost, nontoxicity, sufficiently high density and comparable viscosity.

Jun 19, 2024

By J W. Hedenquist

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Epithermal deposits (Au or Ag dominant, ± base metals) form within ~1 km of the surface in volcanic belts, both arcs and rifts, with the different tectonic settings reflected in distinctly different characteristics. Within arcs, deposits are typically intrusion centred and commonly associated with hypogene advanced argillic alteration, both in lithocaps and as halos to shallow or proximal portions of some veins; such alteration is coupled with processes that form porphyry Cu-Au deposits at depths of ~1–3 km. Introduction of metals is related to the subsequent phyllic-stage overprint; if this fluid rises to the level of the lithocap or into epithermal veins, Au mineralisation with Cu or Ag may occur, associated with sulfate minerals or muscovite. By contrast, Au-rich (both low Ag:Au ratio and bonanza grade) colloform quartz veins form at shallow depths in volcanic rifts, typically within a few hundred metres of the surface, with clay halos and topped by silica sinter if the palaeosurface is preserved. The geologic variability in volcanic belts, including host rocks, structures and hydraulic gradients, means that many epithermal deposits vary from the end-member features of the principal styles. Effective exploration requires familiarity with end-member styles as well as potential variations, plus the mineralogical indicators of palaeotemperature (eg evidence for erosion depth, fluid flow channels). This knowledge helps the geologist in the field to imagine what might be buried and where, and how to best test the target with drilling.CITATION:Hedenquist, J W, 2015. Recent developments in understanding of and exploration for epithermal deposits in volcanic arcs , in Proceedings PACRIM 2015 Congress, pp 11–16 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

Ultrasonic Extinction for High Resolution Particle Size and Concentration Analysis

Sep 13, 2010

The conclusions reached by den Tex after a study of the fabric of some rocks from Broken Hill have been used to support the epigenetic hypothesis for the origin of the ore, first by Edwards (1959, p. 70) and then by Stillwell (1962, p. 131) in his criticism of Segnit's (1961) views. Den Tex claimed that the petrofabric study provided "independent evidence that the ore, at least in its present form, post-dates all events of a diastrophic nature in the area concerned".Repetition of this claim by Edwards and by Stillwell and the lack of any criticism of den Tex's work for more than three years implies its general acceptance by geologists in Australia. Therefore it appears necessary to examine parts of den Tex's paper in detail to show that his, conclusions are unwarranted. The major weaknesses in his study are that1. the petrofabric study was inadequate to warrant any major conclusions, and2. the petrofabric data allow alternative conclusions.Den Tex made a single visit to the field, collected six carefully selected specimens and presented quartz and· biotitepetrofabric diagrams for two specimens, quartz-diagrams alone for three more and included three diagrams of the orientation of c-axes and fractures in one specimen. It is not reasonable to come to firm conclusions about the origin of such a complex area as Broken Hill on such inadequate data, despite den Tex's claim (p. 87, lines 22 and 23) that "a thorough investigation of the quartz-fabric of the wall rock was undertaken".Den Tex's interpretation of each diagram is open to criticism, and alternative (and to my mind, preferable) interpretations may be made. It is impossible to evaluate den...

Jan 1, 1962

ZINC concentrate, produced at Zeehan by flotation from Read Rosebery ore, is also dried and roasted at the same place for the production of a calcine suitable for use in the electrolytic zinc process at Risdon, Tasmania.DRYINGThe concentrate, dewatered to 12% moisture by an American filter, is fed into a dryer, the type of construction of which is similar to that of a duplex Edwards furnace. The dryer is 45 ft. long and 14 ft. wide, and has two rows of nine rabbles each, the two pairs nearest the firebox being watercooled.The longitudinal distance between rabble-centres is 4 ft. The rabbles are rotated at a speed of 3 r.p.m. by a I5-h.p. motor. Zinc concentrate is introduced by a screw feeder, consisting of two parallel-blade conveyors, revolving in opposite directions at aspeed of 31 r.p.m.Draft is supplied by a Sirocco fan, 15 in. intake, operated at 1340 r.p.m. by a 10-h.p. motor. The dust carried by the exit gases is removed in a wooden scrubbing tower, 3 ft. 6 in. x 4 ft. 6 in. x 27 ft. high, to which the fan delivers, and down which water issprayed.Wood (eucalyptus timber) is used as fuel, the consumption per ton of water evaporated being 0.55 :ton. Zinc concentrate from the dryer passed either to trucks for shipment or to Herreshoff furnaces. The portion for shipment is withdrawn at a point half-way down the furnace, being loaded on to a belt conveyor for transfer to railway trucks. The moisture at this point is 7% to 8%.

Jan 1, 1927

WHILE in the employ of the Broken Hill Associated Smelters and the Electrolytic Zinc Oompanies at their South Melbourne Research Station, the writer was detailed to investigate the principles underlying the Parkes Process with a view of determining:1. The Interdependence of the variables:(a) Quantity of zinc required per charge,(b) Temperature of stirring of each zincing,(c) Silver content of the bullion after first zinculg,(d) Silver content of the bullion after second zincing,(e) Silver grade of the crusts produced for retorting, with reference to the method of working the Parkes Process then in operation at Port Pirie.2. The possibility of effecting improvements in the Port Pirie practice of desilverising, especially with respect to:(a) Silver grade of the crusts produced for retorting.(b) Quantity of zinc required per charge.The method of desilverising in practice at Port Pirie was a two-stage zincing.In both zincings the bullion was cooled to its solidification temperature and the silver crusts which separated from the lead were completely removed.The crusts from the first zincing were retorted, and the crusts from the second zincing were returned to the first zincing of the next charge.

Jan 1, 1925

By Kentwell D. J, Cusak C. J, Harvey-Kelly F. E L, M D. Goodz

The Morning Star Gold Mine presents an example of a prolific operation with considerable historical records, mine workings, drill hole logs and countless plans from greater than 20 adjacent mines which have now been consolidated to form the current project. Implementation of 3D computer modelling in the planning stages has provided an additional tool to integrate and refine geological models as a guide to some exploration strategies. It has allowed for a re- interpretation of the host rock units, dimensional constraints, new exploration extensions and provisional resource modelling. The initial consideration of this project was to integrate 135 years of mining history into a single database. Each historic mining area had an unrelated mine grid, often established parallel to the long axis of their main stopes; some were based on magnetic or true north. Survey plans were in chain, imperial or metric units. Through the manipulation and rotation of old grids, previously unrelated mine workings began to form continuous mineralised zones, with unmined portions still remaining in between the existing development. Furthermore the current drillhole database of >433 holes showed numerous confirmatory intersections of new mineralisation. A series of tiered tables were created within a relational database to derive guidelines for assessing data to attribute a Mineral Prospectivity Value [MPV] based on key indicators of mineralisation. Indicator logging now forms the basis of geological descriptions.

Jan 1, 1997

Terramin Australia LimitedÆs Angas Lead and Zinc Mine operates in the unique and picturesque environment of Adelaide Hills, 60 km South East of the Adelaide city centre itself. The mine was granted approval for construction by the South Australian Government in April 2007 and the Process Plant was constructed and commissioned in July 2008. This paper outlines the background to the plant design and the approval process given the close proximity to the local town of Strathalbyn, with a major focus on the commissioning learnings from the Concentrator startup for future reference and a review of the operational performance of the Concentrator throughout the first year of successful production versus design and expectations.

Jan 1, 2009

The widely accepted concept of mineral resources are that they are finite - mining therefore being intrinsically unsustainable. Yet the modern global mining industry continues to grow production at strong rates - how can this be? In reality, mining is a complex industry, starting with exploration, development, operations and then rehabilitation and closure. A recent major study of Australia has shown that for most mineral commodities, exploration continues to find new deposits, or expand resources at existing mines. In parallel, however, there are a number of key 'mega-trends' which are growing in their importance - declining ore grades (or quality), increasing tailings and waste rock volumes, the need for deeper mining, more refractory ore types, increasing energy inputs and higher unit energy costs, increasing pollution issues and, of course, not to forget greenhouse gas emissions issues. This paper will present a detailed case study of the ultimate sustainability of the Australian mining industry - showing long term historical data sets on ore grades, waste volumes and economic resources and placing these trends in light of major twenty-first century issues such as energy supplies (especially Peak Oil), climate change and existing and emerging land use conflicts (eg agriculture versus mining). Australia is a critical case study in the sustainability of mining, as it is a major global exporter of numerous commodities, and this is expected to continue to underpin the ongoing industrialisation of countries such as China and India. The ultimate question begs - can Australia actually meet this fundamental challenge, or will our resources run out, or will we be constrained by environmental issues such as climate change, land use or perhaps water? Rather than a mere optimist's or pessimist's view, this paper will present a range of hard data which underpins the debate about the sustainability of mining this century: ultimately, we cannot assume that the patterns of past mining will continue to work in the future. The sustainability of mining continues to hang in a precarious balance.

Jun 1, 2010

By K B. Quast, A Schuurmans

Laboratory batch rod and ball milling tests were conducted on samples of Heavy Medium Separator (HMS) sinks from Renison Limited. The effects of mill rotation speed, rod volume and ball size on the resulting product size distribution were investigated. Between 48 and 69 per cent of critical speed, the product sizing distribution curves remained very similar, with a finer grind resulting from increasing the speed of rotation at constant grind time. Increasing the rod loading from ten to 53 per cent by volume caused the product size to become finer and more closely sized with a transition occurring at approximately 29 per cent. This was interpreted as a change of dominant grinding mechanism from abrasion to impact. No preferential grinding of the cassiterite was observed. The effect of increasing ball size at constant charge weight was to preferentially grind the coarser particles and generate more intermediate sized particles, whereas the product from a mixed ball charge gave a distribution similar to that obtained when a charge containing only smaller balls was used.

Jan 1, 1998

By D Brett

"Mine waste storages including tailings dams and waste rock dumps represent arguably the biggest risk on a mine site from both physical and geochemical viewpoints, related firstly to structural stability and the consequences of failure and secondly from potential on-going seepage or run-off of acid and metalliferous drainage (AMD). The risks are most likely to increase during operations and continue through the closure and post-closure phases, with the waste storages likely to be the most difficult features to resolve in the mine closure process. Contaminated water quality from tailings dams and waste rock dumps can require treatment "in perpetuity" at a cost of hundreds of millions of dollars. The problem is increasing with ever larger mine operations and waste generation volumes. This paper identifies leading practice methodologies in planning and operating mines and process plants to minimise the risks from tailings storages and how this might also affect waste rock management and even the design of mine excavations. These methodologies require a "big-picture" approach to develop an understanding of the overall issues and identify synergies between the different operational areas on a mine site that can reduce overall risk. With a conservative approach and realistic allowance for future costs it is possible to facilitate decisions at the mine planning stage that can reduce risk and save cost over the long term. This is in contrast to the common approach where each operational area is looking to minimise its own costs with a short-term view. Incorrect mine methodologies can be developed by allowing net present value (NPV) accounting methods to trivialise future closure issues.Methodologies discussed include: Integrated Waste Management - Significant structural improvements to tailings dams can be achieved if the structures can be incorporated into the waste rock dumps. Risk of AMD can also be reduced by utilising the tailings and waste rock effectively. This could go even further to consider the placement of wastes to limit mine void environmental issues; Process Optimisation - Water quality and the nature of potential tailings dam structures can be highly influenced by the geo-chemistry of the tailings. This can be modified by processing, where simple changes such as maintaining separate streams of geo-chemically different tailings rather than recombining them or by initiating further processing to remove problematic minerals such as sulphides; Enhancing Geophysical Properties - The geochemical performance of waste repositories can be greatly influenced by the geophysical properties of the stored materials, particularly the air-water characteristics, which are influenced by particle size, density and permeability. The geotechnical properties can be enhanced by strategic paddock dumping, blending and compaction.These methodologies are demonstrated by case histories.CITATION:Brett, D, 2013. Mine waste risk minimisation by integrated waste management and process optimisation, in Proceedings MetPlant 2013, pp 247-258 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013