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By P Mulvey

"Currently mine process studies and geochemical waste characterisation are considered as two interdependent studies, necessary for the development of the mine and inclusion in the environmental impact statement (EIS). Geochemical waste characterisation will utilise the simulated tailings produced by the mine process studies team to understand the behaviour of the tailings, but the two teams rarely integrate these to develop a coherent and agreed final design.Thorough mine waste geochemical assessments can develop processes to minimise environmental harm, resulting in substantial savings in the decommissioning, closure and rehabilitation phases, and may also be able to address changes in mineral processing methods that can result in substantial savings in process inputs, or even recovery of metal concentrates.Based on geochemical waste characterisation, the full cost of waste management can be calculated and incorporated into the costing of milling.  This allows for a more effective evaluation of the metallurgy.  A number of examples are presented in which substantial improvements have been made from the collaboration of both the metallurgical and geochemical teams during planning and the metallurgical team and environmental team during operations.*This paper is only available for individual download. It is not included in the conference proceedings*CITATION:Mulvey, P, 2013. Optimising metallurgy at the planning stage to minimise environmental impact - a feedback loop from geochemical waste characterisation, presented to MetPlant 2013 Conference (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013

The New South Wales coal industry is a highly mechanised well organised industry which has developed from an annual production of slightly less than 13 million tons in 1950 to over 33 million tons in 1969. Although continuous miners were not introduced into the mines until 1950, by Jillle 1969 the percentage of coal won by these units was 87.3. The paper describes mining conditions in the various coalfields of the State, their complexities and problems and how these have been dealt with. The introduction of fully mechanised long wall faces has presented a challenge which has been accepted and descriptions of systems in use are discussed. Major expansion of the industry is anticipated to meet the requirements of the growing Australian steel industry, for local power generation and to meet the increasing demands of overseas markets.

Jan 1, 1971

By Ho SE, Neil Phillips G, Houstoun SM

There are numerous individual gold deposits in the Archaean greenstone belts of Western Australia, but only 26 have productions and/or quoted reserves in excess of 10 tonnes Au. Most gold production has come from mineralization in shear zones, quartz veins or stockworks in volcanic or intrusive host rocks, particularly tholeiitic basalts or dolerites metamorphosed at sub-amphibolite facies (e.g. Kalgoorlie). Significant prod- uction has also come from BIF-hosted deposits (e.g. Hill 50), and large reserves are quoted for mafic hosts at high metamorphic grade (e.g. Big Bell). Most deposits have marked structural control, great depth extension, and are characterized by zoned alteration haloes of pyritization (with Au), K-metasomatism and carbonation. On the regional scale, most larger volcanic- or intrusive-hosted deposits occur in younger (ca 2.8 b.y.) rift-phase green- stones (Norseman-Wiluna Belt). These belts also have a high prospectivity (36 kg Au/km2 of greenstone belt). Younger (ca 3.0 b.y.) and older (ca 3.5 b.y.) platform-phase green stones of the Murchison and Sodthern Cross Provinces and the east Pilbara, respectively, are progressively less prospective (14 kg Au/km2 and 0.8 kg Au/km2, respectively) and also have progressively smaller deposits. The important regional- and local-scale characteristics of most gold deposits can be explained in terms of a metamorphic- replacement model. In this model, metamorphic H2O-CO2 fluids, focussed by faults and shear zones, infiltrated host rocks and deposit gold at 350 + 50¦C and 1-2 kb, largely in response to fluid-wallrock interaction. In many large deposits, gold precipitation was synchronous with sulphidation of Fe-rich host rocks, but the diversity and abundance of smaller deposits reflects the variety of reactions precipitating gold from ubiquitous, auriferous metamorphic fluids. Regional variations in abundance and size of deposits relate to factors such as tectonic setting, alteration styles and possibly source rocks.

Jan 1, 1986

Characteristics Analysis of a Bastnaesite Rare Earth Mineral for Recovery of Cerium

Sep 13, 2010

Improvement of Phosphate Ore Flotation Performance Through Sized Flotation

Sep 13, 2010

The New Zealand microcontinent is relatively well endowed with gold deposits; its past gold production per unit area of 3.2 kg/km2 ranks high on a world scale. Total recorded production (1857 - 1986) is about 854 000 kg and most of this gold was mined between 1861 and 1920. There has been a strong revival in gold exploration and mining since 1979, with exploration expenditure of around $15 million per annum and a declared gold production in 1986 of 1265 kg (886 kg in 1985). In addition to numerous alluvial gold recovery plants working small to medium sized deposits (mainly in Westland and Otago), there are five medium to large projects that have started production (Martha Hill), or have reached advanced stages of construction (Grey River dredge), permitting (Golden Cross and Macraes) or exploration (Globe-Progress). This summary paper is taken from reviews by Brathwaite et al (1986) and Brathwaite (1988).

Jan 1, 1988

By A Kamkar-Rouhani

The paper describes a mineral potential mapping of gold and other base metals in Mahneshan area, Iran, using geographical information system (GIS), in which, the method of weights of evidence is used to combine spatial data obtained from different sources to make prediction for mineral potential. This is a quantitative tool for mineral resource mapping that can be used to delineate and predict favorable areas for further exploration by using the characteristics of known and similar mineral deposits. In accord with the descriptive model for gold and other base metal deposits, the spatial distribution of 20 known mineral occurrences was used. In addition, digital evidential maps were used in this study. The maps include maps of lithological units, faults and first derivative of total aeromagnetic data, remotely-sensing data of alteration and also geochemical evidential maps produced on the basis of the results of chemical analyses of samples taken from the stream sediments in the area, and analysed for Cu, Pb, Zn, Sb, As, Ag, Au, Ba and Hg elements. The binary maps were produced and then combined with the model of weights of evidence using 20 known mineral occurrences to obtain a final map of the favourable areas for further exploration of gold and other base metals in the study area. The final map is a predictive GIS model of the mineral deposits in the area. An interesting matter about the final predictive GIS model is that the faults are mainly located in favorable areas which possesses the most probability of mineralisation. Therefore, the faults in these areas have priority for further exploration of gold and others base metals.

Jan 1, 2005

This paper describes new research and development currently being undertaken by the CSIRO Mining Technology Group to advance the automation capability of continuous mining equipment in underground coal mining operations. The effort aims at increasing the overall rate of roadway development as well as providing a safer working environment for underground mine personnel. The activity is funded by the Australian Coal Association Research Program (ACARP) and forms part of a larger underground development initiative, known as the CM2010 project. The CM2010 is managed via a consortium of leading mining industry representatives through the Roadway Development Task Group (RDTG). The Task Group has identified three research areas requiring new development in order to realise the CM2010 project objectives: self-guiding (autonomous) continuous miner capability, an enhanced drilling and bolting process and improved mesh deployment. CSIRO's primary role in the CM2010 project is in the development of the autonomous continuous miner guidance capability.This paper reports on outcomes achieved at the half-way mark of a three year research and development project. It details the technical developments undertaken towards demonstration of a 'self-steering' capability to enable a continuous miner to automatically maintain a given mining heading and mining horizon under production conditions. A primary technical requirement of this automated functionality is the means to accurately determine both the location and orientation of the continuous miner in real-time. Testing and validation of the guidance system solution has been implemented using a combination of an instrumentation-grade inertial navigation unit and radar technology. Comprehensive performance evaluations have been conducted using a scale skid-steer mobility platform known as the Phoenix. Results achieved to the present stage of the project are highly promising and suggest that an automated self-steering functionality is achievable under production conditions. This new outcome represents an important move towards implementing a step change improvement for future underground roadway development.

Dec 6, 2010

By B Firth, G OÆBrien, B Jenkins

In coal flotation, particles of different components of the coal such as maceral groups and mineral matter and their associations have different hydrophobicities and therefore different flotation responses. By using a new coal grain analysis method for characterising individual grains, more detailed flotation performance analysis and modelling approaches have been developed. The method involves the use of microscopic imaging techniques to obtain estimates of size, compositional and density information on individual grains of fine coal. The density and composition partitioning of coal processed through different flotation systems provides an avenue to pinpoint the actual cause of poor process performance so that corrective action may be initiated. The information on grain size, density and composition is being used as input data to develop more detailed flotation process models to provide better predictions of process performance for both mechanical and column flotation devices. A number of approaches may be taken to flotation modelling such as the probability approach and the kinetic model approach or a combination of the two. In the work reported here, a simple probability approach has been taken, which will be further refined in due course. The use of grain data to map the responses of different types of coal grains through various fine coal cleaning processes provided a more advanced diagnostic capability for fine coal cleaning circuits. This enabled flotation performance curves analogous to partition curves for density separators to be produced for flotation devices.

Jan 1, 2005

By M A. Rhamdhani, K Avarmaa, A Putera, J Chen, G Brooks

Silicon-based photovoltaic cells are currently the most dominant types applied to convert solar energy to electricity. In solar-grade silicon (SG-Si), the control of boron (B) and phosphorus (P) is very critical. Generally, these elements are difficult to remove into acceptable sub-ppm levels from lower grade Si. This study investigates slag treatment as a process for Si refining, focusing on the behaviour of P and B. The experiments were conducted by equilibrating Si-B-P alloys with 43 wt per cent SiO2 – 47 wt per cent CaO – 10 wt per cent Al2O3 slag under inert atmosphere at 1500°C. Different crucible materials were used (Al2O3, SiO2 and MgO), which determined the primary saturation phase for the system and modified the final slag composition accordingly. The samples were equilibrated and analysed with microanalysis techniques (EPMA (electron probe microanalysis) and LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry)). New standards were prepared and applied in the LA-ICP-MS analyses. Experimental results show that silver is essentially fully dissolved in silicon, as well as most phosphorus with LP ( = wt per cent P in slag/wt per cent P in Si) between 0.1–0.3. The distribution coefficient of boron was measured to be between 1 and 2. The crucible material used had an influence on the phase compositions and slight influence on the distribution coefficients of boron and phosphorus. The experimental results provided new accurate data when considering applicability of slag treatment as a technique for Si refining and Si PV cell recycling.

Jun 19, 2024

By Cawte D. C, Just G. D, Whitchurch K. D

The stringent marketing specifications included in coal contracts mean that coal producers must supply cleaner and more consistent coal than may have been formerly required. Geostatistics has the potential to aid in the accurate estimation of the washability characteristics of coal. A prediction method, the Kriged Service Variable Approach has been developed.A Computer Aided Drafting and Design system has proved useful in the development and application of the approach. The geostatistical approach has been tested against coal geological and borehole data and applications discussed.

Jan 1, 1987

A Process for the Flotation of Chrysocolla

Sep 13, 2010

By Pullen G, Rose M

Continuing Professional Development (CPD) is not just a catch-cry. It is an essential component of every-day life in many professions, including accountancy, law and public administration. Without realising it, many other professions are undertaking CPD activities in an un-structured way, including mining, metallurgy and geology. Examples include Annual and technical conferences of The Institute, Branch-level technical meetings and in-company training and development programmes and technical exchanges. Whilst approaches to date have undoubtedly helped keep the Australian mining industry at the forefront of mining technology, one cannot presume that technological development will stand still. To meet this challenge, human resource development must keep pace, not only to optimize utilization of technological developments, but more importantly to develop firm bases from which new products, processes and technologies can be developed within Australia.

Jan 1, 1989

Constraints on the mineral industry are best treated as issues that have to be understood and managed in partnership rather than in conflict with communities. TheZapopan development at Mt Todd in Australia and the Martha Hill development at Waihi in New Zealand are but two of many recent successful examples at the local level.   However, at the national level, the issues are more complex and more difficult to resolve because the most influential stakeholders are now the urban electorates and governments defer to their perceptions when making decisions and policy. In the developed countries, government policies for the development of mineral resources have been progressively eroded since the early 1970s. At the same time policies for the environment and for native land rights have generally been carried out in a way that has reduced access to minerals and increased the cost and risks for prospectors and developers (Hancock, 1995). Since the end of the Cold War, the lesser developed countries (LDCs) have introduced policies to attract investment in their mineral resources that remained undeveloped under previous unstable or hostile regimes. The increased attraction of these LDCs and the decreased attraction of the developed countries has caused many Australian and North American companies to outlay increasing proportions of their budgets and capital investment in the LDCs.   Significantly, LDC policies for environment protection do not discourage exploration and mine development, Surveys of the relative appeal of the LDCs and the traditional mining countries of the developed world, rate Chile, Argentina and Indonesia ahead of Australia and Canada in terms of risk, delays and ease of doing business (Australian Mining Monthly, February 1994).

Jan 1, 1995

It's long been suspected that there has been an increase in the incidence of premature failure of rock bolts in underground coal mines over the past ten years. As far back as 2002 a study found a possible contributor to such premature failure in some Australian coal mines might be linked to stress corrosion cracking (SCC) (Crosky et al, 2002). That study suggested the low impact toughness could be a major influence on the susceptibility to SCC of different steel compositions. A subsequent study involving laboratory corrosion tests however failed to confirm any link with metallurgical factors (Villalba and Atrens, 2007), a finding that is at odds with field experience. Some mine sites today are still reporting prematurely failed rock bolts to the rock bolt manufacturers; the failures are being identified at SCC induced. To this end a research project has recently been commissioned at University of New South Wales (UNSW), which aims to identify the environmental factors causing SCC, through field test sites and simulating the conditions within an accelerated corrosion laboratory. This paper outlines the methodology that will be used in this study.

Nov 25, 2010

By Burns K. L

Keyboard patterns of hundreds of minor faults with vertical displacements of 3 mm to 2 m occur within the Greta coal seam and cause serious mining problems in collieries. Many of the faults are concentrated in linear zones termed swarms. One swarm is 600 m wide and more than 800 m long and others are of comparable size.The minor faults between the swarms are normal and are relatively widely spaced and show dip-slip movements, but the faults within a swarm are clustered and show strike-slip and oblique-slip movements. Fault swarms ofthis size and frequency have not previously been described from the Sydney Basin or on a comparable scale elsewhere but appear to be a widespread phenomenon in Australian coalfields. The faults are assigned to classes onthe basis of orientation which are then assigned to sequential phases I to IV on the basis of offsetting relations between representatives of each class. Phase I faults are minor thrusts. Phase IT, Ill, and IV faults are concentratedin the swarms and show sinistral strike-slip and normal dip-slip movements. The interference of slickenlines indicates that multiple movements have occurred within a single phase; their order is (i) strike slip (ii) dip slip and (iii) oblique slip. All faults truncate and post-date both cleat and sedimentary "stone" dykes.Phase I minor thrusts trend at a high angle to the Hunter Thrust and are considered to predate the Late Permian movements on the Hunter Thrust. Phase II and III minor faults are younger and may be any age between the latePermian and Tertiary.

Jan 1, 1978

The Pilbara Block is a nucleus of Archaean rocks which lies in the North West Land Division of Western Australia, and it constitutes a mineral province that has been divided into two areas-the West Pilbara Goldfield and the Pilbara Goldfield.In the West Pilbara Goldfield two contemporaneous environments are represented by laterally equivalent volcanic and sedimentary successions which together comprise the Roebourne Group. The two successions are lithologically similar to the classical Warrawoona (volcanic) and Mosquito Creek (sedimentary) successions of the Pilbara Goldfield; but in the West Pilbara Goldfield there is no sign of the erosional break which separates the Warrawoona Succession from the Mosquito Creek succession. The Roebourne Group and the igneous rocks which have intruded it belong to the Archaean Pilbara System.Evidence of preconsolidation movement and igneous intrusion into unconsolidated sediment suggests that tectonism and igneous activity, localized along lines of fracture in an unidentified basement, beganbefore lithification was complete. Movement was primarily vertical, and persisted into the Lower Proterozoic.Vulcanicity and chemical sedimentation, accompanied by a diminution of detr:tal sedimentation, is thought to have caused a relative enrichment in the metal content of the middle part of the Roebourne Group; and the metal may have been remobilized during diagenesis and metamorphism, and localized in zones of dislocation formed both before and after consolidation of the sediments.INTRODUCTIONThe name "Pilbara" has been widely applied in the area under discussion, and to avoid confusion the various uses are summarized below.1. The town of Pilbara, now abandoned, was a centre of mining between 1888 and about 1914. It lies some 90 miles FJSK of Roebourne (Fig. 1).2. The original Pilbara Goldfield was modified several...

Jan 1, 1965

By G Harbort, V Lawson

Mount Isa Mines Limited operates one of the worldÆs largest underground mines in North West Queensland. ItÆs mining and smelting complex produces copper anode, crude lead bullion (containing silver), and zinc concentrate. Copper is recovered in the Copper Concentrator from chalcopyrite ore, converter smelter slag and rotary holding furnace (RHF) slag via grinding and flotation operations. During 2002 a project to optimise cleaner circuit capacity was commenced. Its aims were to minimise copper losses and minimise slag/chalcopyrite cross contamination by reconfiguring existing flotation equipment and the addition of new flotation capacity. To minimise cross contamination a Jameson Cell was installed and dedicated to cleaning of slag concentrates, which had formerly been conducted by three flotation columns operating in series. The flotation columns were re-configured to operate in parallel and dedicated to upgrading chalcopyrite concentrate. In addition a Jameson Cell was installed to reject entrained copper from a prefloat concentrate consisting of talc and carbonaceous pyrite. This paper discusses the logic behind the cleaner circuit expansion, recent test work relating to the Jameson Cell and the installation and commissioning phases. Difficulties relating to the commissioning are reviewed and the solutions to problems are highlighted. The benefits the reconfigured circuit has provided to Mount Isa Mines are also discussed.

Jan 1, 2003

Some low grade South Australian iron ores were classified on the basis of their physical characteristics. Ores from Mount Christie and Billeroo are coarse grained mixed ores; Mount Christie ore could be concentrated by gravity or dry magnetic separation at 10 mesh, but Billeroo ore needed to be crushed minus 36 mesh. Ores from Razorback Ridge and Wilgena Hill are fine grained mixed ores; ore from Wilgena Hill could be concentrated by flotation, but poor results were obtained on Razorback Ridge ore. Malcolm Creek ore is non-magnetic and crystalline, and can be concentrated by flotation, but the deposit is small. Ores from Grants Quarries and Peeralilla Hill are nonmagnetic and earthy and could not be satisfactorily concentrated.INTRODUCTIONThe Geological Survey of South Australia has for several years been undertaking a systematic study of the iron ore resources of the State (excluding the Middleback Ranges) in relation to their geology, reserves, and beneficiation. As part of the latter phase of the investigation samples of the ores have been submitted to The Australian Mineral Development Laboratories (AMDL), and it was the study of these samples which provided the material for this paper.The mineragraphic and metallurgical work was undertaken by several officers of AMDL and the results are contained in unpublished reports submitted to the South Australian Department of Mines. Field data published here was obtained from unpublished reports by G. F. Whitten, Senior Geologist, Iron Exploration, of the Geological Survey of South Australia.

Jan 1, 1964

By A D. Stewart Gillies

Resource rent taxes are taxes which only become effective at such a time as a pre-determined rate of return has been achieved by an operation. Resource Rent Taxes have from time to time been considered for implementation in bothAustralia and New Zealand. The offshore petroleum industry in Australia is already subject to RRT as is the Roxby Downs (Olympic Dam) Mine in South Australia. Both the mining and petroleum taxation regimes in Papua New Guinea include a resource rent tax component called Additional Profits Tax.   The implications of the current form of additional profits tax for shareholder cash returns are that the tax burden on the operation may suddenly increase at some stage in the life of the mine if and when the threshold level of profitability for the tax to be triggered is exceeded. From that point in time onwards the cash return to the shareholders on the capital invested is greatly diminished. For mining companies in Papua New Guinea, the effective tax rate increases from 35% to 57.75% as a result of the onset of additional profits tax. This tax rate penalty is so severe that there appears to be merit in considering the concept of managing profitability through time rather than purely maximising annual pre-tax profits as is currently the case in most mining operations. This would have the benefit of deferring or perhaps preventing altogether the onset of the tax. One possible method for the effective management of profitability is through the control of average mining grade by cutoff grade manipulation.   Traditional cutoff grade theory has usually considered taxation as a direct cost at a fixed or variable percentage of annual profits. As a result of this most analyses are conducted on a pre-tax basis. If tax is included in analyses it is usually present as a time independent function of gross profit. Additional profits tax is both time, and rate of return dependent and therefore not adequately accommodated by currently accepted cutoff grade theory.   A review has been made of the effects of resource rent taxes on both the investment decision-making process as well as possible development and mining strategies which may be employed by mining companies faced with resource rent taxes. The review includes examples based on the structure of additional profits tax which is levied in Papua New Guinea.

Jan 1, 1995