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By Kewu W

Kaolin used as an industrial mineral, especially that in the paper-manufacturing industry, must be of fine size, with high brightness, a low impurity content, and good crystal shape. However, in most kaolin deposits there are various impurities which have a very bad effect on the quality of the kaolin. Therefore, it is necessary to remove these impurities from kaolin ore. Owing to their similar surface properties, the separation of kaolin and iron oxide minerals, especially microkaolin and iron oxide minerals, has been regarded as difficult. The iron oxide minerals often intergrow with kaolin in fine and complicated forms, such as thin films, which make separation difficult. In order to overcome this difficulty, many workers have suggested various treatment methods and obtained great success. Based on research work by Fuerstenau (1980), Huang, Li and Hu (1984), Hui and Wei (1991), Shergold (1978), and Zambrana et al (1974), we have investigated a two-liquid flotation technique for iron removal from kaolin and obtained some success.

Jan 1, 1993

By R Morrison, P Walters, B Adair, V Jokovic

‘Grade Engineering<sub>®</sub> is an integrated approach to coarse rejection that matches a suite of separation technologies to ore specific characteristics and compares the net value of rejecting low value components in current feed streams to existing mine plans as part of a system-view’ (Walters, 2017). Two of these technologies are directly recoverable through screening stages: Natural Deportment and Induced Deportment. The potential for taking advantage of “Natural Deportment” by size following blasting and crushing has been demonstrated for a range of ore types. Simple and low cost screening can in some cases generate a fine product with improved grade and a lower grade oversize which can be directed to leach or to waste. Where an ore body consists of many different ore types, the traditional approach of blending to metal grade will often add to complexity of treatment, which will reduce the effect of “natural deportment” by size.CITATION: Jokovic, V, Walters, P, Adair, B and Morrison, R, 2018. Applying enhanced grade engineering to complex ore bodies, in Proceedings Complex Orebodies Conference 2018, pp 21–23 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 21, 2018

The selection and implementation of the right technology for a project is critical to the future development of the resource industry. It is essential for companies to ensure ongoing competitive viability that where practical new or alternative technology be adopted. Analysis of historical data relating to development of resource-based process plants provides an enlightening insight into the key factors which influence their success or failure. The adoption of new technology does not guarantee the success of a project. The outcomes of this analysis have been used to develop some general guidelines and principles the author believes are useful in the selection and implementation of new or alternative technology in resource projects. This paper is available as a PowerPoint presentation only.

Jan 1, 2006

By P Jonsén, S Larsson, M Parian, B I. Pålsson

The question of effective energy utilisation in grinding mills is not new. There are several conflicting arguments about tumbling mills, whether the efficiency is around 1 per cent or maybe 10 per cent, or even much lower. The energy not used is assumed to be lost as heating of the pulp, the grinding mill body, the charge, generation of shock waves and vibrations, etc. Stirred media mills on the other hand are generally considered to have better energy utilisation, but their energy efficiency is still not that clear. To shed some light on this a pilot-scale, wet stirred media mill was investigated over a range of operating conditions. The wet stirred media mill is a Drais PMH 5 TEX pearl mill fitted with an electric motor at 11 kW. It has been investigated over a range of operating conditions to try to balance the dissemination of the input energy in forms of the net grinding energy, mechanical energy losses, and the heating transferred to the pulp, the mill, the charge, and the cooling water. It is found that approximately 20–40 per cent of the input energy accounts for the grinding process. Also, that the difference between gross and net input electrical energy is mainly disseminated as heating of the pulp and cooling water. Mechanical energy losses appear to be much smaller than the heating effects. The use of a dispersant seems to mainly influence the heating effect.

Aug 24, 2022

By Travis G. A

The Mons Cupri Cu-Pb-Zn deposit is situated within a complex Archaean volcanic sequence dominated by rhyolitic fragmental rocks. This sequence is underlain by a 150 m group of rhyolitic ash flow tuffs with minor conglomerate and sandstone, and is overlain by approximately 180 m of dacite and andesite flows. The Mons Cupri sequence itself consists of several elongate or circular rhyolite domes, flanked by rhyolitic fragmental rocks ranging up to 400 m in thickness away from the domes. The lithology of clasts (typically 1 cm to 1.5 m in size) provides strong evidence that the flanking fragmental unit was derived by explosive eruptions associated with the rhyolite domes. An approximately 15 m thick shale horizon, bleached and silicified at its base, overlies both the rhyolite domes and the frag- mental unit. A south-dipping chloritic pipe-like body, with near-surface dimensions of 1,000 by 250 m and narrowing at depth to produce a cone-shaped cross section, lies within the rhyolitic frag- mental rocks about 250 m north of the largest rhyolite'dome in the Mons Cupri vicinity. Its east west elongation parallels that of the rhyolite dome. Ghost fragments indicate that the material in this fissure is a severely chloritized derivative of the rhyolitic frag- mental unit. The chloritic pipe is overlain

Jan 1, 1973

By A Stradling

For a geometallurgical program to be successful, linkage must be made between the geologists and geostaticians who understand and model the orebody, the metallurgists who determine the value that can be extracted from the different geometallurgical units, and the mine planners who develop and optimise the plan to extract maximum economic value from the resource. One of the primary purposes of geometallurgical models is in the determination of the economic cut-off between ore and waste. Recognition of the level of confidence required in the estimation of grade, throughput and recovery is critical to the planning of a successful geometallurgical program. It also helps clarify the scope of work needed to mitigate risk at each stage in the development of a new mine projectThis presentation provides some of the author’s experience with development and application of geometallurgical models for existing base metal operations. It discusses how geological units defined by lithology, structure, alteration etc, can be translated into geometallurgical ore types defined by mineralogy, ore hardness, and flotation behaviour. Examples of how these characteristics have been used to estimate key economic parameters such as mill throughput and flotation recovery at two brown-field operations are provided. The first example relates to the modelling of metallurgical performance at Teck’s Red Dog zinc-lead mine in Alaska. Prior to 2000, zinc, lead and silver recoveries from a block of ore at Red Dog were either assumed constant, or were varied according to simplistic models. Throughput was not thought to vary substantially between blocks, so an average value was used for each blended stockpile. It is quite possible that some ore-value blocks were classified as waste, and some waste-value blocks treated as ore, as a result of poor understanding of the true economic cut off across the wide range of ore types observed at Red Dog. After an extensive flotation test program, the first assay-based zinc recovery model was developed for the Main pit reserve in 2003.**This is an abstract only. No paper was prepared for this abstract**

Sep 5, 2011

By D J. Black

The process of excavating and mining coal causes fractures in the overlying and underlying strata. The fractures provide pathways for gas released from coal seams and other gas-bearing strata to flow into the mine workings. Coal seam gas typically contains high concentrations of methane with lesser concentrations of carbon dioxide. Low concentrations of other gases such as nitrogen, hydrogen sulfide and ethane may also be present in some coal seams. In certain geological settings, particularly in close proximity to geological structures, such as faults and dykes, the concentration of gases contained in a coal seam can vary significantly between methane-rich to carbon dioxide-rich.In mine design and planning it is vital that mining engineers gather sufficient information to accurately determine the content and composition of the gas present in the coal seam and develop an understanding of changes in these parameters within the planned mining area.The longwall method of mining coal causes fracturing of the overlying and underlying strata behind the retreating longwall face. Where coal seams and other gas-bearing strata are present within the caving zone, gas will be released from the strata leading to contamination of the mine workings. If the rate of gas emission exceeds the diluting capacity of the mine ventilation, the concentration of gas in the mine may exceed the statutory limit, resulting in production delays and potentially unsafe conditions.CITATION:Black, D J, 2016. Planning effective management of gas emissions in an underground coalmine, in Proceedings Life-of-Mine 2016 Conference, pp 44–47 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By S M. W Rajaratnam, P Varma, T L. Sletten

Mining employees undertaking shift work are at considerable risk of experiencing sleep disturbances and circadian rhythm disruptions. In the complex, high-risk environment of mining, these sleep and circadian disruptions lead to adverse impacts on employee health, alertness and safety. Evidence-based tools that effectively target improvements in sleep health amongst shift workers are needed. Variability in work hours and individual differences in the response to shift work mean that a ‘one-size-fits-all’ solution is often insufficient in complex work environments. Currently no interventions provide tailored support for shift workers based on their rosters, personal commitments and sleep habits. Existing technologies, such as smartphone applications and watches, allow sleep monitoring, but their strategies are targeted towards night sleepers, which does not translate to shift work contexts. To address this, our team has developed an innovative digital tool that implements biomathematical models to provide automated, personalised sleep and circadian intervention strategies to optimise sleep, alertness and performance during shift work. The tool uses mathematical models of sleep and alertness regulation that provide physiologically optimal times for an individual to sleep when experiencing circadian disruption. This program of work included co-designed development of a world-first app with shift workers and the examination of the preliminary efficacy of the intervention for improving sleep, alertness and performance.

Apr 16, 2024

By C Catania

Mining companies and operations across the globe typically target best practice financial management, along with a focus on economically driven mine plans. Not only is this inherent in running a successful mining business, but also critical in addressing investor scrutiny. The standards for social and environmental practices is less consistent than this, with most companies adopting standards that are driven through legislative and compliance requirements of the nations in which they operate. Although there is still room for improvement, Australian is a country that stands at the forefront of social and environmental legislation, driving more sustainable planning practices for mining operations, with an ever-increasing focus on mine closure considerations. Of the many nations yet to reach such a legislative position, Kazakhstan is a place where some companies are driving towards world class standards beyond what is government mandated. CITATION:Catania, C, 2018. World-class mine planning for a sustainable future in Kazakhstan Mining, in Proceedings Life-of-Mine 2018, pp 6–7 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By P Cavieres, R Dunlop, S Gaete

El Teniente Mine started the exploitation of the primary rock in the beginning of the 1980s decade, using caving methods. Since the beginning the mining activities have induced seismicity including some occasional rockbursts. Owing to the relevant damages, the mining operations were stopped in some production sectors. This paper describes the concepts that have been used in order to control the induced seismicity based on the strategies for controlling the rockmass breaking process, which depend on mining parameters. It also presents the main concepts applied in the Teniente Sub6 sector design and the experience collected during its sector exploitation.

Jan 1, 2000

Nickel laterite HPAL circuits are known for their complexity and have presented a large number of challenges to process engineers worldwide. An attitude commonly encountered by the author is that the beneficiation of the ore is relatively simple and that the difficult problems are in the realms of hydrometallurgy. On a number of occasions beneficiation has become the 'poor cousin' in the process design phase. Another common theme is that significant difficulties are encountered when beneficiation circuits are started up, invariably slowing the ramp-up of the remainder of the circuit. In some cases the problems impact on throughput for a long period and can require major rectification capital. The HPAL Ni laterite projects encountered each have their own set of beneficiation problems that need to be understood before an appropriate circuit can be designed. This paper will discuss a range of design issues including geometallurgy, ore characterisation through laboratory testing, the application of appropriate sizing and analytical procedures, the selection of appropriate unit operations, materials handling of plant feed and products and setting meaningful plant design requirements.

Jan 1, 2008

By B Hu, B Zhang, J Wang, H Ma, D Liu, L Han

Zeolites are potential carriers of slow release fertilisers due to their unique phenomenon for salt occlusion. A comparative study was performed on the capacities of potassium nitrate (KNO3) occlusion in molten KNO3 treated synthetic 4A and 13X zeolite molecular sieves with main channel sizes of 0.41 x 0.41 nm and 0.74 x 0.74 nm respectively. The results show that in a laboratory setting, the treated zeolite 4A contained 13.57 per cent of occluded KNO3 and the treated zeolite 13X did not contain any. This was confirmed by the regular release of K+ and NO3- during washing both treated mixed samples with water and by their IR spectra and TG analysis. There are also changes of the relative intensities of peaks in X-ray diffractograms of both treated zeolite samples. K+ release from molten-KNO3 treated zeolites in deionised water and simulated soil solution shows that release of K+ from KNO3 occluded in zeolite 4A are slow and steady. Proper size fit between the channel size of zeolites pore and the size of K+-NO3- ion pair of KNO3 is the decisive factor for zeolites to occlude KNO3.

Jan 1, 2008

The considerations which led to the decision to_ install discs at the Dampier Pellet Plant of Hamer ley Iron Pty. Ltd. are described. Initial testwork showed that the ore could be ground dry in open circuit to a Blaine index of 2500 cm2/g and that it pelletized readily. The various design criteria including diameter, slope, speed, motor size, depth of sidewall, feed point and water spray location were then determined. Plant performance after commissioning is described including the various problems encountered and the modifications since carried out to overcome them. The main problem was quickly identified as disc feed rate control. Various bin and bin feeder modifications were tried to overcome the effects of the fluidising characteristics of the dry ground ore. Other factors found to affect disc operation are ore size distribution, additives and operator competence.

Jan 1, 1974

The history of the rail and mining industry in Queensland over the past century is inseparable. Indeed it was mining that led to the construction of the line west from Townsville and that shaped its current alignment. The discovery of gold at Charters Towers started construction of the Great Northern Railway west from Townsville in 1879, with completion to Charters Towers in 1882. The line was extended to Hughenden in 1887 and to Cloncurry in 1907 - driven by copper mines both to the south west and the north west of Cloncurry. The mining industryÆs association with funding the construction of rail lines to service their individual mines began in this area when the Hampden and Mount Elliot mine companies agreed to pay 50 per cent of the cost of the line from Cloncurry. The line to Selwyn was completed in 1910. Copper mining saw the construction of many other rail lines in the Cloncurry area in the 1910 - 20 period before copper prices slumped. Included in these lines were the Malbon to Duchess line and the line to Kajabbi and beyond.

Jan 1, 1998

The demand for minerals will grow strongly to satisfy the needs of an increasing world population for materials and energy. The technical problems involved in producing these minerals will be daunting and the engineers who will have the responsibility for designing and controlling the mineral production processes must have a high level of skills. This will place a heavy responsibility on the education system. A small number of large, well equipped university departments dedicated to mineral processing and having a close working relationship with the mineral industry, and an international orientation, will be much better placed to meet the needs than a large number of small ill-equipped departments which find it difficult to remain viable in modem universities. Courses in mineral processing must be designed to meet the scientific and technological needs of industry and full use must be made of innovative educational techniques such as video conferencing in delivering the courses. The concept of a major international network of major mineral processing departments which is designed to make best use of scarce academic resources is important and should be considered by the International Committee of the IMPC.

Jan 1, 1993

By T W. C Stambolie

Coalmines, like any other mine, generally involve the classic three-staged approach to mining studies; namely concept, pre-feasibility study (PFS) and feasibility studies (Cusworth, 2012). Subsequent to these studies, and in instances parallel to these studies, the commitment to an environmental impact statement (EIS) is made in order to secure both state and federal development consent. In recent times, the sentiment to both mining and coal is changing whereby the traditional approaches to mine planning and economic evaluation is complicated by evolving environmental legislation, expectations and time frames. It is all too common to take shortcuts in the development of projects in order to create the perception of cost savings and expediting the delivery timeline. Atkins (2016) points out that: boards of so many small to mid-tier mining companies, and a few majors, focus on relentless project delivery too early in the project process, with so little time and effort applied to risk analysis and option development. Unforeseen risks can cost any timeline or budget far more than the effort required assessing and mitigating these. The ultimate risk to any feasible coal project is that of environmental approval and achieving development consent.CITATION:Stambolie, T W C, 2016. A black canvas – planning a greenfield coalmine in New South Wales, in Proceedings Life-of-Mine 2016 Conference , pp 31–35 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By L E. Howard

Micro-computed tomography (Micro-CT) is an X-ray imaging technique that produces high-resolution 3D computerised ‘virtual’ models of geological specimens based on the X-ray attenuation of different materials in the specimen. The ‘virtual’ specimens are made up of voxels, the 3D equivalent of pixels, each assigned a gray value based on X-ray absorption. Micro-CT has enormous potential for allowing non-destructive, digital analysis of structure and composition when the mineralogical phases can be digitally separated. However, variation in X-ray flux between scans results in highly variable grayscale values for identical materials. Consequently, materials usually have to be segmented manually, which is subjective, inaccurate, labour-intensive and time consuming. Here we present a protocol and imaging software package that can be used to accurately and precisely extract quantifiable information in a repeatable and objective fashion. The software will allow the separation, visualisation, measurement and analysis of spatial and volumetric distribution of different mineral phases without damaging the specimen. This paper explains the potential use of this protocol and software package to ultimately allow automatic segmentation and quantification of gold in drill core samples, removing subjectivity and inaccuracies from data processing.

Sep 5, 2011

By Y Peng, D J. Bradshaw, X Chen

At NewcrestÆs Telfer gold mine, a strategy of regrinding pyrite rougher flotation concentrates has been proposed to increase gold recovery and reduce cyanide consumption in the CIL circuit. The regrinding will be followed by an additional copper/gold flotation stage, where copper minerals need to be separated from pyrite. However, although the minerals are well liberated, the separation of chalcopyrite from pyrite in the cleaner stage is not always straightforward. The surfaces of the fine particles, produced during regrinding, are more easily oxidised and contaminated than coarse particles, directly influencing the particle floatability. The depression of pyrite is difficult in the cleaner stage as well due to copper activation, a process which is also highly dependent on the grinding environment. In this study, different grinding media, including mild steel and stainless steel, was used in the regrinding to produce different regrinding chemistry, such as, pH, Eh, and iron hydroxide contamination. The effects of regrinding conditions on chalcopyrite flotation and its separation from pyrite were studied. It was found that the stainless steel grinding media, which produced an oxidising environment, was more beneficial for the separation of chalcopyrite from pyrite after regrinding. The mild steel grinding media had a detrimental effect on both chalcopyrite and pyrite flotation. This study addresses the importance of choosing suitable regrinding conditions in the pyrite and copper flotation circuit.CITATION:Chen, X, Peng, Y and Bradshaw, D J, 2012. Effect of regrinding conditions on the flotation of chalcopyrite and its separation from pyrite in the cleaner stage, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 279-286 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

Olympic Dam Operation is located in the Stuart Shelf Geological Province approximately 520 km north-north-west of Adelaide in South Australia. It is estimated to be one of the worldÆs top five copper orebodies by size and the biggest single occurrence of uranium. The deposit was discovered by Western Mining Corporation in 1975. Exploration was based on a conceptual model for the formation of sediment hosted copper deposits together with gravity and magnetic anomalies.The capital cost of the current expansion is estimated to be A$ 1.64 billion. The underground expansion includes a total of 36 km of lateral development, a railway haulage system delivering ore from a series of ore passes to a new crusher station and a significant increase in ventilation capacity and mine services.In the current underground expansion the mining method will essentially remain unchanged. The ore handling system will incorporate some recent advances in technology, improving efficiency and safety standards.Major infrastructure excavations are designed by a team of engineers attached to the Olympic Dam Expansion Project and a number of consulting groups. Once the expansion is fully completed it is expected to increase the current annual underground production level from 3.4 Mt to 9.0 Mt of ore by the year 2000. Mine design engineers working for the Olympic Dam Operation have recently completed a three year final design plan to achieve this target.Access to the existing mine is through the decline and Whenan shaft. The Whenan shaft was originally sunk as an exploration access and later upgraded for hoisting. The 4 km long service decline connecting to the Whenan shaft was later constructed to accommodate the increase in service demand. The Robinson and Sir Lindsay Clark shafts were developed at later stages to cater for the hoisting during and following the expansion lead up.

Jan 1, 1999

By D E. Ralph, D-J Kim, G-J Ahn, Y-H Rhee

The amount of discarded dry batteries are presently found to be increasing globally and waste cathode active materials of the lithium ion battery industry are among them. Hydrometallurgical operations are being applied to recover the valuable metals from these waste batteries. To find an economic and environmentally friendly process, the bioleaching process was applied in the present investigation for recovery of valuable metals. Its principle is the microbial production of sulfuric acid and simultaneous leaching of metals. Bioleaching of spent lithium ion secondary batteries, containing LiCoO2, has been studied in this investigation. A new method for recovery of cobalt, potentially the basis of an economic and environmentally friendly process was examined. The present study has been carried out using chemolithotrophic and acidophilic bacteria Acidithiobacillus ferrooxidans, which utilises elemental sulfur and ferrous ion as the energy source to dissolve metals from spent batteries. Bio-dissolution of cobalt was found to be faster than lithium. The effect of initial Fe(II) concentration, initial pH and solid/liquid (w/v) ratio were studied in detail. Higher Fe(II) concentration showed a decrease in dissolution due to co-precipitation of Fe(III) with the metals in the residues. Similarly, at higher initial pH values and higher solid/liquid ratio (w/v) metal dissolution was found to be inhibited. The optimised conditions for bio-dissolution were solid/liquid (w/v) ratio û 10 g/L, initial Fe(II) concentration û 3 g/L, elemental sulfur û one per cent (w/v) and initial pH û 2.5. In the optimised conditions, cobalt dissolution was observed to be about 60 per cent, whereas that of lithium was ten per cent after 20 days. A first order kinetic model was derived to study the rate of dissolution of both the metals.

Jan 1, 2006