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In order to understand the technique, basic theoretical principles of radiation emission and in- strumentation theory are reviewed. Methods of surveying, reduction of data and interpretation are outlined. Other applications of the technique (e.g. in airborne geological mapping), as well as its specific use in uranium exploration, are discussed. By means of case history-type examples the successful applicant of gamma-ray spectrometry, as a tool in Australian mineral search, is demonstrated.

Jan 1, 1969

By P Hawke, J Hurst, B KrapeP

Hancock Prospecting Pty Ltd (HPPL) drilled two deep diamond stratigraphic holes (ECD0001 and RHD0296) within the eastern Fortescue Valley in the Pilbara of Western Australia. Located south of the Roy Hill Iron Ore project, the holes aimed to define the stratigraphy of the Marra Mamba Iron Formation (MMIF) of the Chichester Range and its south-dipping extensions below recent cover. Previous attempts to define the MMIF of the Chichester Range have resulted in differing interpretations due to the data available at the time.The unweathered MMIF beneath the Fortescue Valley in the HPPL drill holes is characterised by dolomitic carbonate interbedded with stilpnomelane-rich shales, chert and banded iron formation (BIF) with hematite staining. This intersection equates to ~75 m of carbonate-facies iron formation, as opposed to the ~230 m thick oxide-facies BIF and shale sequence encountered south of the Fortescue Valley.Various detailed geological core analyses and interpretations from ECD0001 and RHD0296 were integrated with regional diamond and reverse circulation (RC) holes from across the Fortescue Valley. Interpretation of the data indicates that the eastern Fortescue Valley MMIF represents a thinned thickness sequence of the whole formation. The MMIF of the Chichester Range and Fortescue Valley has gamma logs that correlate strongly in parts to the type section used for MMIF south of the Fortescue Valley. Therefore, the outcropping MMIF in the Chichester Range represents an eroded equivalent of the æreducedÆ thickness MMIF observed in ECD0001 and RHD0296.Data from deep diamond drill holes across the valley, from the Hamersley Basin to the Carawine Basin, were correlated. The correlation shows that the depositional site of the MMIF in the HPPL diamond drill holes is consistent with a proximal ramp setting, in which iron-rich shales wedge up-palaeoslope and shelf-derived carbonate turbidites wedge down-palaeoslope. Not only is it the occurrence of these shales that define the MMIF, but they also determine the northward potential to develop orebodies, as they are the source of iron from which iron-rich oxides and carbonates of metamorphic or diagenetic origin form.CITATION:Hurst, J, KrapeP, B and Hawke, P, 2013. Stratigraphy of the Marra Mamba iron formation within the Chichester Range and its implications for iron ore genesis at Roy Hill - evidence from deep diamond drill holes within the East Fortescue Valley, in Proceedings Iron Ore 2013 , pp 91-106 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By M Edwards

The paper outlines the successful application of some of the on-belt technologies available from Scantech International Pty Ltd and how these have provided benefits in a number of mining and mineral processing operations. Effective process control requires real time analysis so quality can be fed back to the previous process and fed forward to a subsequent process. A range of on-belt analysers that allows for full stream, continuous, non-contact analysis of conveyed materials is available to achieve this. Real time results can provide timely information for effective process control. Benefits of on-belt analysis systems become more evident once the true variability of material quality and moisture content in conveyed flows is measured. To obtain economies of scale in mineral processing operations large material flows are achieved using conveyors. The cost and effort to sample representatively increases as conveyor flows increase. One sample may represent a few tonnes or up to 10 000 tonnes of material. The turnaround time between sampling and availability of sample analysis data does not allow real time process control. Tonnage flow rate, moisture content and elemental or mineralogical composition are required to perform effective process control of most conveyed streams. Tonnages can be effectively measured using belt weighers. The analyses derived from small samples supplied by conveyor-based sampling systems contain high variability. On-belt, continuous analysers see all the material and, through short term compositing of analyses, supply less variable results. Real time analysis helps operators develop a better understanding of material variability. Analysers can be effectively utilised to improve the consistency of product quality through bulk sorting and blending control. Many existing users of the technologies have gained competitive advantages through their ability to supply a more consistent quality product to the market.

Jan 1, 2008

By R Baumgartner

The Canahuire deposit is a recently discovered Au-Cu-Ag epithermal deposit in Southern Peru. A geometallurgy program is a key study element of the project Feasibility study. Metallurgical, mineralogical, and comminution studies have been completed over a suite of samples, spatially distributed among the various geological/ore domains. The early stage of Canahuire presents challenges as there is a lack of metallurgical information to guide geometallurgical sampling, in contrast with an established deposit at a more advanced stage of development or mining. Nevertheless, the available information will assist in the development of geometallurgical domains for Canahuire in order to ensure that future metallurgical, mineralogical, and comminution test work is representative of the deposit variability. This supplementary knowledge will be able to predict important metallurgical parameters which will be incorporated into a geometallurgical model to spatial predict material types, metallurgical recovery and through put. The information obtained will be a valuable addition to the future mine plan, influencing process design, engineering design, plant operation, operating and capital costs, and ultimately will reduce project development risk.

Sep 5, 2011

By S Wright, W Bruckard

The current status of battery collection and recycling schemes in Australia are explored in light of current developments in product stewardship and increasing pressure to decrease materials going to landfill by originating equipment manufacturers. Used consumer batteries, both single cycle and rechargeable contain a mixture of valuable metals and potentially toxic materials that may become a resource/revenue stream to offset the cost of disposal/recycling. Although the volume of batteries discarded in Australia is modest compared to other global population centres, the expected increase in battery use with increasing equipment portability and future developments in the automotive industry, provide an opportunity to recycle. The requirements for a battery recycling facility in Australia and the most promising processing platforms that may exploit the resource with enough flexibility to cope with battery developments and market trends, are explored.

Jan 1, 2006

By E Widzyk-Capehart, P Vallejos, R Asenjo, J Ruiz-del-Solar

Throughout the minerals industry, it is evident that a new wave of technological innovation is needed as the mining sector looks for ways to achieve higher security and safety as well as higher production rates with less investment. Innovation has always been one of the key factors in achieving success within the mining industry. However, its importance will be especially relevant in the coming years if negative trends in commodity prices and new challenges facing the industry (lower grades, deeper mines and economy of scales) are to be overcome and the future sustainability and profitability of the sector ensured.The drive towards fully autonomous operations has begun, with the implementation of automated systems in both surface and underground operations. However, these automated systems are currently planned and realised with well-defined automated tasks within structured environments and isolated spaces. Currently, there is no interaction between automated systems, manned systems or humans, which creates physically isolated environments.For fully autonomous and continuous operations, the automated systems need to operate in environments that enable flexible interactions between automated machines, tele- and manually operated machines and humans.In this paper, we address the automation paradigm considering the synergistic collaboration between humans and automated systems. In this paradigm, humans and machines would interact in a flexible, collaborative and synergistic way without the need for isolation. The implementation of this concept within mining operations will have to be underpinned by science and technological developments and will require adaptation from many fields, including robotics, automation, distributed systems, communication, human factors, pattern recognition and mine design.The paper also presents the research and development work being undertaken at the University of Chile’s Advanced Mining Technology Center, in collaboration with the Chilean mining industry. This will provide the basis for flexible interactions between humans and technology-based systems towards a future of autonomous and continuous mining systems.CITATION:Ruiz-del-Solar, J, Widzyk-Capehart, E, Vallejos, P and Asenjo, R, 2015. Synergistic collaboration of humans and automated systems – innovative steps towards fully autonomous and continuous mining systems, in Proceedings Third International Future Mining Conference, pp 83–94 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By D François-Bongarçon

The theory of sampling (TOS), and therefore representative sampling, is based on three fundamental principles: sample correctness, which handles the search for non-bias; segregation, the effects of which must be eliminated or minimised; and variance control to help achieve the desired reproducibility. After briefly reviewing these very few, albeit essential first principles of Gy’s TOS, the state-of-the-art in TOS is examined through the prism of these principles and the prospects for the future are explored, with suggestions for further research where relevant. Regarding segregation, which is currently the focus of much research, new orientations are proposed. For correctness, which takes on a major importance when it comes to sampling devices, some new, important principles that have been put forth by recent research, are described in details.CITATION:François-Bongarçon, D, 2014. State of affairs and current research trends in theory of sampling fundamentals, including segregation and correctness, in Proceedings Sampling 2014 , pp 11–16 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

By Swayn G. P, Floyd J. M

BHAS, together with the G.K. Williams Laboratory, and Ausmelt Pty. Ltd., has examined a number of possible alternatives to conventional silver cupellation in gas fired reverberatory furnaces. Of these alternatives, a Sirosmelt furnace was preferred for both technical and economic reasons. Small scale work on Sirosmelt processes was carried out at the G.K. Williams Laboratory at Melbourne University in 1985/86. Pilot scale work was carried out at the Ausmelt plant in Melbourne in July 1987. Board approval for construction of a full size plant was received in October, 1988, and construction of the plant is currently underway. The plant is expected to provide significant savings in operating costs and silver inventory. Hygiene around the furnace should also be greatly improved. An increase in cupellation rate of at least ten times is expected, compared with the conventional reverberatory furnace.

Jan 1, 1989

By Y Lanwin

The Australian mining sector is undergoing a significant transformation with the adoption of advanced technology to the operational landscape. This has highlighted a critical disconnect between our traditional educational systems and the skill requirements of working with these advanced technologies. This paper aims to provide a behavioural science analysis of how the traditional manufacturing mindset, deeply rooted in our educational frameworks from primary to tertiary education, registered training organisations (RTOs), and in-house learning and development, is misaligned with the needs of today’s technologically advanced mining operations. Originating in the industrial revolution, the manufacturing mindset prioritised efficiency, mass production, and the division of labour. In educational institutions, this translated into an emphasis on rote learning, linear examinations, and a rigid adherence to processes and procedures. Such a system, while effective in producing a workforce suited for repetitive and predictable tasks, falls short in fostering skills like problem-solving, adaptability, flexibility, and coping with change – skills that are increasingly vital in a mining sector dominated by automation, robotics, and AI. The paper discusses how the focus on disciplined adherence to standard work procedures and processes in educational and training programs has inadvertently stifled creativity and autonomy in learners. This issue is compounded in the workplace, where employees, having been conditioned to operate within strict guidelines, now face the challenge of adapting to environments where autonomous decision-making and creative problem solving are crucial. In essence, the traditional approach to education and training has prepared individuals for a world of work that no longer exists. This paper advocates for a whole of pipeline approach, grounded in behavioural science, to revamp mining education and training. It highlights the importance of understanding and influencing the behavioural aspects of learning and recommends for an approach that promotes diversity, critical thinking, and adaptability, preparing the workforce to excel in the rapidly changing landscape of the Australian mining sector.

Sep 1, 2024

By Z Li, Z Yan, T Htet, S Zhang

During the pyrometallurgical processes, a substantial quantity of high-temperature ironmaking and steelmaking slags, generated at temperatures ranging from 1400 to 1600°C, is wasted, as the heat contained in these slags is released into the environment during the tapping process without effective utilisation. On the other hand, a significant amount of energy is required to reheat the cold materials for the manufacturing of glass and mineral-wool, often necessitating the addition of high-silica materials to facilitate the production process. In this study, an innovative approach is presented to harness the heat present in molten metallurgical slags to directly produce new raw materials for glass and mineral-wool manufacturing while simultaneously reducing energy consumption and mitigating CO2 emissions. The theoretical amount of waste glass that can be effectively added in the process has been estimated via thermodynamic calculation. Experimental assessments were conducted to examine the impact of high-silica waste materials on the dissolution, melting and fluidity. Potential recipes for glass and mineral-wool manufacturing were suggested and an assessment of the energy savings, and reduction in CO2 emissions with manufacturing of glass and mineral-wool using this innovative approach were included. It was determined that the processes could lead to a reduction of over 26 kg of CO2 emissions per 100 kg of new material used, primarily due to the utilisation of heat from slag and the accelerated smelting process.

Aug 21, 2024

By Hebblewhite B, Humphreys D

An experimental mining project has been carried out in the Collie Basin to demonstrate the safe operation of total extraction mining techniques in the underground mines of the basin. To achieve this, it was necessary to design and install a means of controlling or removing groundwater so that goafing of the overlying strata could be safely achieved as part of the mining operation. The site chosen for the experiment was a triangular panel adjacent to Western No 6 (WD6) underground mine, which includes the 3 to 4 m thick Wyvern Seam beneath 130 to 180 m of overburden. The test area abuts a major fault on the downdip side. The overburden and underburden sequences include several horizons of permeable sandstones which form major aquifers. Water problems have long been recognized in all underground mines in the Collie Basin, and have previously prevented the successful application of total extraction mining. Following extensive hydrological investigations, dewatering and depressurization systems were designed to dewater the immediate roof aquifers and to depressurize aquifers higher in the sequence and in the floor. This would enable stable roof conditions to develop and controlled goafing to be achieved. The roof dewatering/depressurization procedure involved a combination of in-mine vertical roof drainage holes and conventional dewatering bores constructed from the ground surface above the mining trial area. The dewatering system was installed and operated for 29 months before the commencement of mining. Mining was eventually successfully completed in two trial panels using a retreat Wongawilli extraction system using bridge conveyors and continuous miners. Water inflow into the mine workings was channelled to a constructed sump area at the lowermost corner of the panel and pumped to the surface via vertical sump bores. The dewatering and depressurization measures adopted were successful in permitting the first controlled and systematic total extraction recovery of coal from the Collie Basin. This trial mining exercise demonstrated the potential for increasing substantially the recovery of coal from the Collie Basin, where previously recovery rates of around 30 percent from underground mining were commonplace, using only bord and pillar methods.

Jan 1, 1988

By M Edgar, G Pattemore, M Auad, K Job, A Job, S Gale

In recent decades, significant advances have improved the modelling techniques for predicting slope failure. Predicting failures is vital in open pit mining due to the significant risk posed to personnel and equipment from unstable pit walls. Failures not only cause harm and damage to people and equipment but also cause delays to production and subsequently increase operational costs. Coupled with improvements in modelling techniques, utilisation of advanced scanning systems, such as high-definition imagery from UAVs has enabled faster and more precise mapping and modelling. However, one key element required for accurate slope stability modelling and monitoring is the ability for mine geotechnical engineers to have an accurate understanding of the mineralogy and moisture content of slopes, in real-time. To address this challenge, research has been undertaken to utilise hyperspectral imaging across a broad spectrum, combined with high-definition imagery, and LiDAR to scan slopes for minerals and moisture content. In addition to accurately mapping mineralogy and moisture, the data must be collected autonomously and remotely to ensure ongoing safety. The results show that there are many direct and indirect benefits from this new technology, including the ability to monitor slopes at a safe distance and in real-time, improved accuracy of modelling, detection of risks, and improving the automation workflow for geotechnical engineers. The paper presents recommendations for the implementation of the technology in open cut mining environments.

Jun 22, 2022

By T Suwa, S Ishida, J Xue, S Fuchida, H Shimada, Y Aoki, C Tokoro

Pyrite depression with prolonged pre-conditioning treatment in high salinity water has attracted much of researchers’ interest in recent years considering the increased utilisation of multiple stage flotation, closed water circuits, clay minerals, and sea water in flotation plants. In this study, the role of calcium (Ca)/magnesium (Mg) precipitates in stabilising the dissociative ferric hydroxy-xanthate (FHX), and its effect on modifying the balance of hydrophobic/hydrophilic species on the pyrite surface were primarily investigated. The total amount of extractable Fe-bearing species on pyrite concentrates and tailings after floatability test was quantitively determined using ethylenediaminetetraacetic acid (EDTA) extraction tests combined with inductively coupled plasma optical emission spectroscopy (ICP-OES). A more evident accumulation of extracted-Fe in pyrite concentrates rather than it in pyrite tailings was observed at both pH 9 and 10.5 when pyrite was pre-conditioned in Ca/Mg-bearing solutions for 360 min. Fourier transform infrared (FTIR) spectroscopy showed the main xanthate derivatives changed from di-xanthogen (1155 cm-1 ) to FHX (1167 cm-1 ) on the oxidised pyrite samples that were preconditioned in Ca/Mg-bearing solutions. Scanning electron microscopy-energy dispersive spectrometry (SEM-EDS) suggested the preferential accumulation of FHX upon secondary Ca/Mg-bearing precipitates as reflected by the higher Fe/S ratio together with the decrease of O element herein after xanthate conditioning. Although the hydrophilic secondary Ca/Mg/Fe-bearing minerals on the pyrite surface generally deteriorate pyrite’s floatability, the upper section of these secondary hydrophilic aggregates is partially covered by FHX alongside with further multilayer-adsorbed di-xanthogen. The precipitated Ca/Mg-bearing precipitates promotes the immobilisation of dissociated FHX derived from the reaction among iron oxyhydroxides and xanthate anions upon the localised secondary Ca/Mg/Fe-bearing minerals via acid–base complexation. Therefore, this phenomenon alleviates the hydrophilic modification of secondary Ca/Mg/Fe-bearing minerals to pyrite considering the immobilised FHX upon localised precipitates shows a slight hydrophobicity, and meanwhile, the upper FHX benefits the multilayer adsorption of di-xanthogen via the interaction among their inner hydrophobic alkyl chains.

Aug 24, 2022

By P Ritchie, E H. Briese, N A. Currey

Kidston Gold Mines, located in semi-arid North Queensland, Australia is currently in its closure phase. Highly innovative and comprehensive rehabilitation strategies were employed at the site, including the direct revegetation of the surface of the tailings storage; the construction of a tailings sediment entrapment pond; the construction of a spillway to drain large rainfall events from the surface of the tailings; the construction of store/release covers over the tops of the waste rock dumps; the sheeting with oxide waste rock of the waste rock dump slopes; the partial back-filling of the initial Wises Hill Pit with waste rock and thickened tailings produced from the subsequent Eldridge Pit; the partial flooding of Eldridge Pit following the end of mining; and the construction of wetland systems to treat contaminated tailings and waste rock dump seepage. These closure strategies involved the careful consideration of water management. Specific water management issues included understanding the water balance of the tailings dam; the operation of the tailings dam sediment entrapment pond and spillway; understanding the water balance of the store/release waste rock dump covers; the importance and sustainability of vegetation on the tailings, store/release waste rock dump covers, and on the sheeted waste rock dump slopes; the level and quality of water in the partially flooded Eldridge Pit; and the treatment of contaminated seepage in the constructed wetlands. The seasonal and highly variable rainfall experienced in this semi-arid climate posed a number of challenges for the management of water on the site post-closure. The paper details these challenges and highlights how they were resolved over the period leading up to and following the end of mining.

Jan 1, 2003

By S M. Gover

Estimating the probability of failure for embankments is not intuitive. It requires not only an appreciation of the strength of the embankment, but an understanding of the variability and uncertainty in the strength parameters as well. These additional aspects are, in themselves, relatively new to most practicing engineers, and therefore require some discussion.This paper discusses the concepts of probability and uncertainty, and presents a reliability-based numerical experiment, together with a literary study and collation of some of the author’s historical slope stability analyses, to investigate whether a direct relationship between safety factors and probabilities of failure exists for certain levels of uncertainty in strength parameters. In doing so, a useful tool is presented whereby knowing the safety factor of a simple slope or embankment with a consistent level of uncertainty, one can infer an approximate probability of failure.CITATION:Gover, S M, 2018. Linking safety factor to probability of failure, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 384–396 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By K W. Bian, Y M. Liu

Tongkuangyu Copper Mine is currently the only mine in China employing block caving. It comprises two large orebodies known as the No 4 orebody and the No 5 orebody. They are approximately 50° in dip angle, 80 to 240 m in width and 800–1000 m in strike length. The two orebodies are separated by a distance of 110–130 m. Production with block caving originally, ie Phase 1 project started at Tongkuangyu from the first undercut at a depth of 200–300 m below the ground surface and designated as Lift 810 m in late 1989 and has continued to the present. During the last 25 years Tongkuangyu has mined three lifts: Lifts 810 m, 690 m and 530 m. The previous two lifts utilised a slusher process with an annual designed production rate of 4 Mt. In this context the lift name represents the elevation of track haul level.The Tongkuangyu Phase 2 project serves for two lifts (ie Lift 530 m and 410 m) under the elevation of 690 m and the annual designed production rate is 6 Mt. Since the orebody is approximately 50° in dip angle, it is originally designed that production at Lift 530 m is comprised of one main extraction level and two auxiliary extraction levels in the footwall and undercutting is started from one end of the extraction footprint forward to another end, which is from north-east to south-west.Production at Lift 530 m started from March 2011 and reached to 6.39 Mt in 2013 and 6.9 Mt in 2014. Additionally, Tongkuangyu improved block caving processes and used modern mining equipment, which differ from the previous two lifts. Blastholes for undercutting and drawbell-preparation are now drilled using jumbos. The blasted ore is transferred to the underground crushing station via 10 t electric load-haul-dumps (LHDs) and then delivered to surface via a belt conveyor 3200 m long.Due to increasing ground pressure, a consequence of mining depth increase, stress abutment and inadequate support, significant damage occurred at the Tongkuangyu Copper Mine with production at Lift 530 m. This resulted in significant production delays and rehabilitation costs. A series of improvements have since been implemented including an advanced undercut sequence and increased ground support. All of these improvements have allowed Tongkuangyu to alleviate ground control issues, reduce operating costs and ensure safe production.CITATION:Liu, Y M and Bian, K W, 2016. Production at Lift 530 m of Tongkuangyu Copper Mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 385–392 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By D Hillier, A Giblett, K Parker, V Ramsell

Kalgoorlie Consolidation Gold Mines (KCGM) operates the Kalgoorlie Super Pit open cut, Mt Charlotte underground mine, Fimiston process plant and Gidji Roaster facility for joint venture partners Newmont Mining Corporation and Barrick Gold. In 2004, the Fimiston plant was upgraded by the addition of gravity concentration to the Fimiston and Mt Charlotte grinding circuits, including the installation of a central intensive cyanidation reactor to process the gravity concentrates. The gravity project was justified after detailed analysis demonstrating an expected increase in overall gold recovery of approximately one per cent, in addition to reduced elution costs and reduced gold inventory in flotation concentrate stockpiles. The gravity circuits were commissioned in August 2004, and have since consistently recovered 10 to 20 per cent of the gold present in the KCGM ore, delivering a reduction in coarse gold losses equivalent to 0.45 per cent additional metal recovery and contributing to improved metal accountability.CITATION:Giblett, A, Hillier, D, Parker, K and Ramsell, V, 2012. The impact of gravity gold recovery at Kalgoorlie Consolidated Gold Mines, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 199-206 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By J Karlovšek

Civil engineering infrastructures are often subjected to different types of natural and mechanical activities. These influences may result in serviceability or even in stability of structures due to material deformations, increased water content within the materials used or the formation of internal or adjacent cavities that may threaten the infrastructure. Construction practices can lead to development of such defects in the form of cavities. In civil engineering it is crucial to detect these variations in material properties and to detect the presence of defects. However, as they are often hidden from view, these attributes may be difficult or impossible to target with traditional testing methods. For these reasons rapid geophysical methods, such as ground penetrating radar (GPR), are increasingly being used. At the University of Queensland (UQ) GPR is used for detection of voids and cavities which have been caused by an over excavation of the earth pressure balance machine (EPB) operating in a closed mode.A variety of numerical simulations using the finite-difference time-domain (FDTD) methods and preliminary experiments have been carried out in order to specify information about the nature, type, size, location and other characteristics of targets to be detected by GPR. In doing this the difficulty of interpreting GPR data, which is mainly due to the complexity of the factors involved in multiple possible solutions of the observed features, can be overcome.

Mar 8, 2011

By L Köresaar, J Moilanen

With lower and increasingly variable Fe grades in iron ore resources, the monitoring of Si, Al, Mg and other light elements to meet quality requirements is gaining importance in the iron ore beneficiation industry. The high cost per manual assay and associated manpower requirements often limit the frequency of shift composite samples and laboratory assays. Furthermore, the shift composite assays represent past performance of a plant but are not useful for immediate reactions to feed variations, detection of equipment malfunctions or process control. Automated online analysis of light elements radically reduces the cost per assay and provides repeatable, timely data for process analysis, control and optimisation.A light element online slurry analyser, based on laser-induced breakdown spectroscopy (LIBS) optical emission technique, will be presented. This paper discusses the analyser design for the iron ore industry and also reviews the performance of the analyser against the manual laboratory. Additionally operator safety, user friendliness and maintenance requirements are discussed.A case study will also be discussed in this paper. The sophisticated measurement technique has been implemented in an industrial automated analyser and sampling system to allow for slurry measurement for up to 12 sampling points. However, careful selection of the sampling points and implementation of the sampling system is required for smooth operation.CITATION:Köresaar, L, Timperi, J and Moilanen, J, 2015. Optimised process control in iron ore via online analysis of light elements, in Proceedings Iron Ore 2015, pp 511–518 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

The last decade has seen a very rapid development in TBM tunnelling. Some trends are purely technical or economical and others relate more to preferences of different interests. Power levels have more than doubled and thrust levels too. Shield machines are developed to be able to handle harder rock and the open TBMs are made more feasible for `difficult' rock. What is right and what is wrong is more a matter of opinion, but one thing is certain: TBMs now are a useful tool and no longer an experimental work-shop for the enthusiasts.This paper highlights some recent developments and indicates some probable future ones. A few features that have increased the open TBMs' ability to cope with ever harder rock and also to overcome problems with poor rock are discussed in detail, using the Atlas Copco JARVA Mk 27 -the most powerful TBM built so far - as a reference.

Jan 1, 1993