Search Documents

By A T. Job, M L. Edgar, P R. McAree

Characterising ores in-pit and in real-time presents a significant value opportunity for the mining industry. Hyperspectral imaging systems are proposed as an enabling technology to achieve this real-time characterisation. This paper considers the application of a hyperspectral imaging spectrometer mounted on a shovel. We define the performance requirements for such a spectrometer and associated subsystems during a typical dig-load cycle. The relatively high swing rotation speed of the shovel requires approximately video-rate exposure times to achieve good spatial resolution. We analyse a selection of components against these requirements and find that suitable commercial spectrometers, detectors and optics appear fit-for-purpose. Automated, real-time spectral classification systems are also available, with only relatively modest requirements for processing power. The paper argues that at near peak solar illumination, a system for field deployment at the required sensitivity is viable using only commercial off-the-shelf components.CITATION:Job, A T, Edgar, M L and McAree, P R, 2017. Real-time shovel-mounted coal or ore sensing, in Proceedings Iron Ore 2017, pp 397–406 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

Implementation of Fine-Screening in Preparation of KGHM PM SA Sandstone-Carbonate Copper Ore for Flotation

Sep 13, 2010

By L A. Maslov

We have considered the following characteristics of the crust and upper mantle of the Pacific Belt: seismic wave velocity anomalies, mechanical stress and shear deformation rate fields, heat flow and the pattern of metallogenic provinces of the Belt. It has been noted that there exist certain .regularities in distribution of the above mentioned geophysical characteristics and metallogenic zones within the Belt, displayed by prevalence of the lithophile elements in the Asia-Australian part of the Belt, and of the chalcophile ones within the American part.

Jan 1, 1995

In recent years there have been many changes in mine ownership due to the on-going rationalisation towards larger mining companies. Larger companies inevitably find it hard to manage small mining operations and in many cases smaller mines do not fit corporate resource, production and profit criteria. Smaller companies are more suited to managing these medium or small scale mines and are tendering for the purchase or lease of mines that larger companies wish to dispose of. In addition to these factors there has also been a trend (especially in Western Australia) for mines to continue operating at ever increasing depths. This in turn has led to more mines operating in high stress environments and experiencing damaging seismicity. Assessing the viability of seismically active mines from a takeover or purchase point of view should involve analysing the risk profile of every aspect on mining that could be affected by adverse seismicity. This includes assessing current and alternative mining methods, mine designs, support systems, extraction sequencing, monitoring and blasting. This paper includes discussion on items that need to be assessed when considering the purchase of seismically active mines, with experience gained from some recent studies in Western Australia. In these cases it was apparent that quantification of previous seismic history on itÆs own was a totally inadequate method of assessing minewide seismic risk potential. A more holistic approach is required, taking into account all aspects of relevant data, all the minewide effects of seismic activity and all possible means of mitigating those effects.

Jan 1, 2002

Beneficiation of Nickel Lateritic Ore from Montes Claros de Goißs, Brazil Beneficiation is a key factor for both technical and economical aspects of industrial processing of nickel lateritic ores. A combination of comminution, classification and concentration stages are usually used to upgrade the metallurgical plant feed, thus resulting in both capital and operating cost reductions. This paper describes the testwork conducted on Montes Claros nickel lateritic ore in order to investigate the potential for upgrading. A comprehensive laboratory testing program included crushing, scrubbing, screening, grinding, gravity separation and attritioning, for both saprolitic and limonitic ore types from the Montes Claros deposit. The results indicated a clear potential for such an upgrade, which was later validated in a pilot plant program.

Sep 13, 2010

By P S. Datta, V N. Misra

Higher bed height up to 680 mm, including 30 mm hearth layer of sized return sinter and high suction below the grate bars up to 1400 mm WG have resulted in increasing the productivity to a level of 33 t/m2/day and reduced coke rate to a level of 46 kg/tonne sinter. The ferro-wastes like blue dust, flue dust, mill scale, collection from dust catcher and gas cleaning plant, etc have been successfully added in charge mix to produce quality sinters. In this paper, brief description of the work done at Regional Research Laboratory (CSIR) in last few years and two case studies are discussed including the successful development of pan sintering units.

Jan 1, 2002

By L Dixon, J Carter, K Auyong

Fourier transform infrared (FTIR) spectroscopy and other near infrared (NIR) tools have been used in the bauxite industry for many years. Infrared spectroscopy exploits the differences in chemical composition and lattice structure to produce a characteristic response. Spectral devices, such as those from ASD Inc and the HyLoggerTM, provide qualitative mineralogical data targeted towards hydrated minerals detected in the near and short wave infrared region. The FTIR spectrum extends into the mid and thermal infrared range and can therefore respond to the presence of silicates and oxides, in addition to hydrates and carbonates.The key to successful utilisation of infrared spectra, however, is the interpretation methodology. In this study, FTIR spectra were calibrated against quantitative X-ray diffraction data for the determination of the mineralogy of iron ore. A full pattern profiling machine learning technique was utilised for the calibration, and the assessment of the regressions determined from an independent validation set. The abundance of key minerals – hematite, goethite, kaolinite and quartz – were determined and the results correlated against X-ray fluorescence assays and loss on ignition data. The results of the study indicate that spectral techniques using a full-pattern profiling machine learning approach and artificial neural networks can be used successfully to obtain objective and quantitative mineralogical data to support field observations and analytical results for iron ore resource modelling. A comparison of this technique to the cost, quality and timeliness of other quantitative mineralogy tools is also made.CITATION:Carter, J, Auyong, K and Dixon, L, 2017. Determination of iron ore mineralogy using Fourier transform infrared spectroscopy and machine learning, in Proceedings Iron Ore 2017, pp 519–528 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By E Widzyk-Capehart, T Bednarz, O Daud, N Cutmore

The interest of industry, in particular future mining, is pointing towards the use of novel visualisation systems to improve the operational efficiency of user interfaces. While the technologies used to enhance operators’ experience are advancing, the implementation of novel visualisation paradigms within mining operations is trailing behind other industries, particularly health and aviation. In this work, we present a number of initiatives and use cases of immersive virtual and augmented reality systems that can fit within the mining context. These ideas represent a step towards new platforms that might increase the efficiency and safety of mining operations through applications such as 3D panoramic video monitoring technology with annotated information coming from big data analytics and visual analytics processing engines. However, while the technologies are used in a variety of training settings, their application in the working environment is lagging behind. This paper presents examples of scientific visualisations that could be applied in a mining context to extend the possibilities of operators’ cognitive abilities and working efficiency. They are intended to foster a discussion within the mining community to move beyond the training realm and into the operational environment.CITATION:Bednarz, T, Widzyk-Capehart, E, Daud, O and Cutmore, N, 2015. Effective immersive visualisation systems for mining applications and beyond, in Proceedings Third International Future Mining Conference, pp 31–36 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By J Benn, V Kuznetsov, G Timms, A Spain

Earthen covers are now widely used in the mining industry to control the generation rate and/or release rate of low quality drainage from piles of sulfidic minewastes. Covers are usually designed to reduce the water infiltration rate and in some cases may also reduce the oxygen flux to the underlying sulfides. Engineered covers have only been used since the 1980s, however, and there is very little field data on their performance in the longer term. This lack of information has implications for the degree of confidence that can be placed on the predictions of the environmental impacts of sulfidic minewastes, for the acceptance of close-out criteria by regulatory authorities and for the financial liability of the mining industry. Covers were placed on sulfidic waste rock dumps at the abandoned Rum Jungle uranium mine during 1984 - 1985. These covers were designed to reduce the water infiltration to less than five per cent of incident rainfall by both water shedding and storage-release mechanisms. Regular monitoring by the Australian Nuclear Science and Technology Organisation (ANSTO) demonstrated that the covers performed better than the design criterion for around ten years, but infiltration rates have subsequently increased. There is a 66 per cent probability that the infiltration rate now exceeds five per cent of incident rainfall. The cover on the largest pile, WhiteÆs heap, was sampled in pits dug at eight locations. Sampling was carried out at the end of the monsoonal wet season and again at the end of the ædryÆ season. This, together with laboratory testing, enabled cover performance to be assessed against five criteria: design, construction, cover material characteristics, physico-chemical characteristics and biological characteristics. We are of the opinion that the design of the cover was suitable to achieve the objectives of stability, water shedding, storage-release, and provision of a substrate for vegetation growth. Over most of the surface of the heap, the construction of the covers, drains and erosion prevention structures was in accordance with design specifications. However, several small and localised bare patches on the upper surface of WhiteÆs heap coincide with a reduced cover thickness, which is likely to have been due to poor construction in those patches. The construction of covers on minewastes is dependent on an adequate source of material meeting design specifications. From our limited examination, it appears that there was shortage of material for each of the three zones û a lower impervious clay layer, the moisture storage-release layer and the upper erosion-resistant layer for vegetative growth. An indication of this was that the upper layers in some areas were observed to be thinner than specified. We are of the opinion that this shortage of suitable material has been responsible for some of the changes observed ten years after emplacement. Physical and geotechnical testing indicated that the cover materials no longer meet the original specifications. In particular, the permeability at the 8 locations was found to be greater than specified, by up to several orders of magnitude. The higher permeability may explain the higher observed rainfall infiltration and moisture content of the waste rock. This increased permeability appears to be due to a combination of biological and physical processes û galleries formed by termites and ants and an extensive system of shrinkage/desiccation cracks formed by the development of a polygonal blocky structure involving the entire lower clay layer. The desiccation cracks may fill with coarser illuviated materials and form a conduit through which roots access the underlying waste rock. Measurements were made of oxygen flux into the heap as cover layers were excavated in the pits. They indicated that the full cover currently reduces the oxygen flux to 20 - 23 per cent of that into bare waste and that this reduction seems to be proportional to the cover thickness. It was also found that the oxygen flux into the cover is about four times higher at the end of the dry season than at the end of the wet season and that the difference is due primarily to the difference in moisture content of the cover. Recommendations are made for the design and construction of covers.

Jan 1, 2003

By J D. Goldsworthy

The McPhee Creek bedded iron deposit is a recent discovery made by Giralia Resources NL (Giralia) in the northern Pilbara of Western Australia. The deposit lies 30 km north of the town of Nullagine along the southeastern margin of the East Pilbara Granite-Greenstone Terrane (EPGGT).The McPhee Creek area is located in the Kelly Greenstone Belt in the southeastern part of the EPGGT. The Archaean aged greenstone belt consists of volcanic and sedimentary sequences including the Warrawoona Group and the Gorge Creek Group. The McPhee Creek iron ore deposit lies within banded iron formation (BIF) rocks of the Gorge Creek Group. The structure of the McPhee Creek area is dominated by a northeast trending, upright synform (Sandy Creek Syncline) and associated folding that is truncated by northeast trending faults in the east. Iron ore mineralisation is predominantly stratabound and follows the dip of the bedding – however, in some areas, particularly in the southwest of the deposit, mapped steep to moderate dips of bedding planes are at odds with underlying fl at mineralised zones in drill sections. Zones within the deposit that contain substantial thickness of iron ore correspond to areas of complex folding suggesting structural control and iron enrichment in fold hinges. Petrographic analyses confirm mineralisation is goethite dominant and the deposit is strongly supergene enriched.Giralia initially identified iron ore potential in the McPhee Creek area through the presence of a small known channel iron deposit (CID) mesa. Giralia began exploration in 2008 by re-drilling a portion of the CID (subsequently named Crescent Moon) and reported a small low-grade Inferred Mineral Resource. Target generation in the wider area utilising Geological Society of Western Australia maps and Ikonos satellite images identifi ed strongly ferruginous outcrops associated with major structures along an 8 km long range located 2.5 km to the west north-west of the Crescent Moon CID deposit. In late July 2008, a total of 62 rock chip samples were collected during a helicopter supported sampling program conducted at McPhee Creek. Samples taken from haematite-goethite enriched BIF and canga zones outcropping intermittently over the 8 km length of the western and central areas of the prominent range assayed up to 63 per cent Fe. These zones represent the discovery outcrops and surface expression of the McPhee Creek main range iron ore deposit.Follow up sampling, geological mapping, bulldozing of access tracks and ramps and reverse circulation (RC) drilling commenced in September 2009. A maiden Inferred Mineral Resource was announced by Giralia to the Australasian Securities Exchange (ASX) on 15 December 2009.The current Indicated and Inferred Mineral Resource at December 2010 stands at 260 Mt grading 56.2 per cent Fe, 0.12 per cent P, 6.7 per cent SiO2, 2.3 per cent Al2O3 and 9.5 per cent LOI at a 50 per cent Fe cut-off. McPhee Creek is one of the largest iron deposits found in Archaean BIF in the northern Pilbara.

Jul 11, 2011

By N Weerasekara, M Powell, P Toor

The effect of liner wear on SAG mill performance has gained much attention in recent years. It is commonly observed that the three key performance criteria of SAG milling; throughput, power and product size all improve as the liner wears.The increase in throughput is generally ascribed to the increase in the grate apertures and the increase in mill volume due to the wear of these components. Whilst the decrease in product size is attributed to the reduction in lifter height and angle, resulting in more breakage by means of attrition and abrasion.Though it is widely acknowledged that the wearing of liner components such as Lifters, Plates and Grates have a significant impact on mill performance, their individual contribution to changes in mill performance has been unclear, and resultantly lead to questions like; what percentage of the throughput increase can be attributed to the increase in mill volume (plate wear)? and how much can be attributed to the increase in grate aperture (grate wear)?It has been found that through the use of grinding surveys, analysis of production data and JKSimMet it was possible to separate the effects of changing liner profile, increasing mill diameter and increasing grate aperture on the mill performance allowing for the quantification of each.The outlined methodology allows for both troubleshooting of problem liner components which reduce milling efficiency in their wear life as well as providing a basis for a more quantitative approach to liner design and reline scheduling.CITATION:Toor, P, Powell, M, Hilden, M and Weerasekara, N, 2015. Understanding the effects of liner wear on semi-autogenous grinding mill performance, in Proceedings MetPlant 2015, pp 150–161 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By L H. G McClean

Diversity, equity and inclusion are often cited as ‘important priorities’ by mining companies and industry organisations in their public presentations and reports, but is the minerals industry really making strides forward? The mining industry is the least gender diverse industry in Australia (WEGA, 2023). Women make up just 22 per cent of the mining workforce and mining has a gender pay gap of 15.1 per cent (WEGA, 2024a). Only 8 per cent of the CEO roles are female and 20 per cent of boards have no female members (WEGA, 2023, 2024a). Gender diversity, equity and inclusion is a highly topical issue with the recent release of the Respect@Work report, Western Australia Parliamentary Inquiry as well as the publication of company specific workplace culture reports and the national legislative changes to implement a positive duty for organisations to prevent sexual harassment in the workplace. This comes at a time of a skills and labour shortage in the minerals industry as well as declining geoscience study and participation. This is a perfect storm for our future workforce. Governments, industry associations, networks and companies are developing and supporting initiatives to make strides towards equity and inclusion, with some shining examples on both an industry and company level, but the dial is only moving slowly and, in some ways, going backwards. Every company is unique, but every company can review and support gender diversity, equity and inclusion. Actions to progress gender parity could include establishing a clear company position; ensuring that this position is cascaded throughout the company with appropriate training; reporting and reviewing gender participation as well as supporting positive workforce initiatives and a positive culture with a people-centric issues reporting process. At the industry level, there are clear gaps in the support for gender diversity and inclusion including a national voice and ‘one-stop-shop’ to support women in the industry and provide resources. Recommendations include improved co-ordination and collaboration of support for women as well as improved promotion of the suitability (and safety) of the industry for women. The new independent organisation, Women in Mining and Resources Australia (WIMARA) has the objective to address the challenges of gender diversity and inclusion as well as foster co-ordination, co-operation and collaboration between the different stakeholders and state or territory groups and amplify reach. To deliver the future workforce that the minerals industry needs, the time is now for the industry to make some giant leaps for womankind.

Sep 1, 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

Fine Gravity Separation in the Reflux Classifier, Exploiting a High Shear Rate, Laminar Flow Mechanism The Reflux Classifier is used in the gravity separation of particles over a broad range of particle sizes. The device consists of a fluidised bed zone, with a system of parallel inclined channels above. The inclined channels provide a significant hydraulic advantage over conventional fluidised beds via the so-called Boycott Effect (Boycott, 1920). This paper describes a new advance in fine gravity separation based on the high shear rate and laminar flow profile that arises when closely spaced inclined channels are deployed. As reported recently (Galvin et al, 2009a), a powerful density based separation mechanism develops from this arrangement, suppressing the effects of particle size. In this paper we focus on two areas, firstly the application of the separator in the laboratory for batch fractionation of particles of varying size and density to determine the grade recovery curve and hence the liberation, and secondly the step change in separation performance achieved on a continuous steady state basis when closely spaced inclined channels are used. The variation in the separation density with particle size decreases significantly, and the Ecarte Probable Error (Ep) remains at low levels over a broad size range.

Sep 13, 2010

The Ekati Diamond Mine is located on permafrost terrain in CanadaÆs Northwest Territories. The mine rock consists of: diamond-bearing and barren kimberlite; and surrounding waste rock such as granite. The kimberlite occurs in several vertical æpipesÆ that are, or will be, mined using open pits. Early predictions of drainage chemistry at Ekati identified the potential for ARD due to sulfide oxidation from both waste rock and kimberlite. This was surprising for the kimberlite, because neutralisation potentials (NP) are typically hundreds of kg CaCO3 equivalent/t. However, subsequent testwork showed that substantial portions of the NP ædisappearedÆ quickly, apparently due to the unusual non-carbonate mineralogy. In any case, additional predictive work concluded much of the rock was benign and there would be no ARD. Shortly after mining started, ARD appeared from both the waste rock and kimberlite, although a few years passed before the company and its consultants recognised that at least some of the acidic water was ARD. Numerous other processes have been put forward as possible explanations for the remaining acidic drainage, although none have been either confirmed or eliminated. Because: the causes of the ARD and acidity are not known; no causes have been eliminated and more have been added; drainage chemistry was not predicted accurately; and future mining will encounter similar rock. I believe the Ekati Diamond Mine needs high-level assistance to understand current chemistry and to avoid problems with future drainage. Organisations like INAP, MEND3, and universities could provide this assistance.

Jan 1, 2003

By G J. Corbett, T M. Leach

A continued exploration programme has further defined the geology of the Tolukuma vein system, verified the resource indicated by Newmont, and identified potential for additional mineralisation. The resource at Tolukuma Hill, designated as zone C, is a mine recoverable 432,000 t at 18.1 g/t Au & 46 g/t Ag. Mining will be by a combination of open pit and underground at a rate of 100,000 t per annum. Processing will be by SAG mill, gravity circuit and CIL plant. A diatreme breccia, localised at an intersection of structures and a relationship of gold to base metal sulphides, are indicative of a strong porphyry association. Typical epithermal features such as crustiform banded quartz and quartz pseudomorphing platy calcite are also present and locally contain lesser gold mineralisation. Pre-existing dilatant structures have acted as a host to the ore fluids, resulting in the formation of the semi-continuous Tolukuma-Gulbadi veins over a 1100 m strike. A fluid flow model suggests that mineralizing fluids were sourced from a diatreme margin and migrated laterally along dilatant structures. Bonanza gold grades are interpreted to be derived through fluid quenching in the flexure between a hanging wall split, which hosts much of the Tolukuma Hill resource, and the feeder graben structure. Thus, the relationship between the pre-mineral structural geometry and fluid upflow at the margins of a diatreme breccia, controls the ore setting.

Jan 1, 1995

The sedimentary basins of this region developed in the collision zone of thePacific Ocean plate and the continent. Stresses were transmitted thorough wedge-like lithospheric blocks, such as the Okotsk Sea, East Kamchatka, Aleutian and other smaller blocks. Compression and inversion were more active at the boundaries: ***INSERT EQ*** and ***INSERT EQ*** in places. Tension, rifting and the increase in the rate of sedimentation were marked in P1-2, P3, N12, and also in N2 û Q in places. Structural plan changes of the sedimentary basins and possible oil, gas and fluid migration occurred more actively at the boundaries: ***INSERT EQ***.

Jan 1, 1995

By D Reid, J Vinod, M Rahman, A Fourie, T Vo, J Ayala, A Russell

This paper reports on an industry and Australian Research Council funded research project, TAILLIQ, that is a joint initiative between four Australian Universities. The paper discusses the accuracy with which the critical void ratio can be determined for a given tailings; it does this by presenting the results from a ‘round robin’ study in which 18 geotechnical laboratories around the world participated, testing the same tailings (sampled from a gold mine in Western Australia). The results were variable, although a reasonable number were very similar, as described in the paper. The paper provides additional test data for sandy silt gold tailings recovered from a sponsor’s site in Australia, including preliminary calibration chamber test data, results from direct simple shear tests and characterisation tests to determine unsaturated geotechnical properties.

Jul 1, 2021

By J Fisher, M Castro, A Hariyadi

The train haulage system being designed for PT Freeport Indonesia’s Grasberg Block Cave (GBC) will be located within the mine at an elevation of almost 3000 m above sea level on the west side of the island of Papua, Indonesia. The developing block cave is beneath the active Grasberg Open Pit and will transport 160 000 t of ore per day from multiple chute galleries to the underground crushing plants. The design entails 28 km of rail and 119 ore chutes, which will be brought online over the course of ten years.The train haulage system will be driverless and fully automated. Sequentially, the system includes remote controlled rock breakers at the top of the chute grizzlies, followed by remote controlled chute loading of the trains, then autonomous train haulage and autonomous unloading. An overhead catenary system (OCS) will power the locomotives, which are equipped with on-board batteries to drive through the loading and unloading sections. Service locomotives with drivers move material-laden freight cars in and out of the service shaft, destined for workshops, the magazine and batch plants. Service locomotives are also used for haulage level maintenance. Highly reliable and redundant control and communications systems are required to manage 12 trains in simultaneous operation.This paper provides an overview of the train haulage system’s technical complexities and the associated support systems interactions. The paper also highlights the project management issues and successes of this globally sourced project.CITATION:Hariyadi, A, Castro, M and Fisher, J, 2016. Automated train ore transport, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 563–570 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

Over recent years the trend in Australia has been towards the definitions of sustainable development which emerged from the 1992 Rio Summit of retaining a commitment to ecological integrity, but also incorporating social and economic dimensions of sustainability. Sustainable development may be seen as maintaining and enhancing:natural capital: defined as all natural resources, both environmental and those of traditional economic value; manufactured capital: made by human kind; including produced goods, infrastructure and built environment; human capital: defined as the health, well-being, intellectual capabilities and spiritual welfare of individuals; and social capital: defined as social relations and institutions within and between societies, their norms and functionality (Ameef, 2002). This paper will endeavour to assess the challenges and opportunities facing the professionals and their Institute in the minerals industry in Australia because the MMSD Global and Regional Australia Reports do not, in the authorÆs opinion, adequately address the æhuman capitalÆ input into the current or future development of the minerals industry, in particular, the sustainability of the professionalsÆ skills, knowledge and experiences in a global context.

Jan 1, 2002