Search Documents

By P Kittler

In the spectrum of mining-related disciplines, geometallurgy sits between resource geology and metallurgical engineering. Unlike its neighbours, it is a relatively young discipline and its concepts, procedures and techniques are still evolving. Relevant geometallurgical issues differ from one deposit to the next so there is no single template that can be used in all situations, meaning that geometallurgy programs are nearly always customised and tailored to the deposit and the situation.Over time, a number of key mistakes are seen to emerge regularly. The eventual impact of these mistakes can vary from suboptimal performance of mine and plant to complete failure of the operation. For instance, poor characterisation of ore lithologies and their spatial distribution can have negative impacts on processing plant throughput. However, when combined with failure to identify critical blending constraints it can result in a totally inoperable plant.A number of common mistakes committed during geometallurgical programs are discussed and some preferred alternative approaches are suggested

Sep 5, 2011

Mining and mineral processing makes a vital contribution to AustraliaÆs national export income, and our society today is critically dependent on its products. Despite the importance of this industry, its operations often come under scrutiny because of its high potential impact on local environments û both social and ecological. The challenge for the minerals industry today is to make the most responsible and best possible use of the national resource base, maximising overall resource utilisation.Research efforts and industry implementation of improvements have been moving in this direction for a considerable time already, and the industry has a long history of process innovation and improvement in Australia. Examples range from the early development of gold cyanidation and mineral flotation to more recent work undertaken under the auspices of AMIRA or through the various CRCs and research organisations such as the AJ Parker CRC for Hydrometallurgy, the Cooperative Research Centre for Mining Technology and Equipment and the Julius Kruttschnitt Mineral Research Centre.However, the nature of research and innovation in the mining and mineral processing sector is changing, as the industry itself copes with the pressures introduced by globalisation, industry consolidation and commodity price cycles. Large firms that have historically maintained a tradition of corporate technology and a culture of innovation are moving to outsource their technological and research competencies and are adopting æfast-followerÆ mentalities. At the same time, the challenges of sustainable development that need to be addressed are many-faceted, multidisciplinary, and require a holistic approach for significant achievements to be realised. Many sustainability issues, particularly those pertaining to environmental and safety issues, are shared across large sections of the minerals industry, and are seen as æindustryÆ problems beyond the scope of a single company.In this environment, collaborative research efforts are becoming the dominant mechanisms for building on past innovations and ensuring the continued success of the mining and mineral processing industries within a framework of sustainable development.

Jan 1, 2004

Mt. Whaleback, the property of the Mt. Newman Joint Venturers, contains more than one thousand million long tons of high grade hema- tite averaging 64% Fe, ranging from 70%, the grade of absolutely pure hematite, to 54%. The ore occurs in the Dales Gorge and Joffre Members of the Brockman Iron Formation. The interbedded shale bands common in other orebodies occurring in these horizons are seldom more than a few inches thick and are commonly partially enriched to about-35% Fe. In the generally hard, massive hematite orebody, the gangue minerals tend to break preferentially to the fines, or -6 mm product, and for this reason it is of a somewhat lower grade than the lumpy product. The control of the chemical qualities is concentrated on the fines product for it has been found that maintaining the iron and alumina levels in this product ensures that all chemical specifications are met in both the lump and fines products. Physical qualities are monitored to ensure that the physical quali- ties of decrepitation and degradation of the lumpy product are maintained at levels accept able to the buyers.

Jan 1, 1973

By I T. Ross

Sampling drawpoints in block cave mines has been a contentious issue for many years. Doubts have been expressed as to the validity of the process used at most mines. This paper outlines the sampling practice commonly in use, discusses the resulting issues associated with reconciliation and drawpoint closure decisions. The paper also looks to the future and highlights issues for some block cave mining operations currently planned to have in the order of one thousand active drawpoints. It is likely that these operations will require a new approach to drawpoint sampling. There are several potential technologies currently available although some appear to be better suited than others to replace the current approaches. CITATION:Ross, I T, 2012. Sampling in block cave mines, in Proceedings Sampling 2012 , pp 81-86 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

By T Mizuta, D Ishiyama

The Vienna Wood hydrothermal is hosted by mid-oceanic ridge type basalt in graben morphology and is located in the Central Manus Basin. The hydrothermal field is about 300 metres in diameter and consist of a sulphide mounds and tall huge death and active chimneys. From the three distinct ore types collected from the Vienna Wood site, the dominant ore minerals recognised are pyrite, wurtzite, sphalerite, chalcopyrite, Fe-oxide and gangue minerals of anhydrite, gypsum, barite and silica. The consistencies in the paragenetic sequence and in the spatial distribution of the sulfides across the three ore types suggest that similar hydrothermal process exist across active and death chimneys. Fluid inclusion studies reveal a homogenisation temperature of 190-260¦C and an average salinity of 5.1-5.4 wt per cent NaCl equiv. The pH of the hydrothermal fluid ranges from 4.2 to 6.1. Bulk chemical analyses indicate that the mineralisation in the Vienna Wood can be classified into the Zn-(Cu-Pb) type of mineralisation. The tenors of the ore and mineral assemblage resemble those of the Mid-oceanic ridge system and ancient ophiolite hosted massive sulphide deposits of Cyprus and Oman.

Jan 1, 2002

By J-H Shin, Y-S Jung, D-J Youn, G-J Bae

This research is to grope for a method to reduce high pore pressure taking place on tunnel shotcrete lining, especially in underwater tunnels, effectively by utilising a new concept of patternised pin drain. Accordingly, the patternised pin drain system is investigated numerically in order to confirm to the effect of reduction of pore pressure by the pin drain and its effective application. Installation of pin drain shows considerable reduction in the figure of pore pressure. It is found through 2D numerical modelling that the change of pore pressure, according to the shape and the location of pin drain, is sensitive by the sequences of the change of location > the change of length > the change of angle degree. In the results of investigation in 3D modelling, the pore pressure is the largest in the centre of the interval among pin drains, and it is possible to obtain an ideal degree of longitudinal angle and an interval by investigating pore pressure taking place on the lining.

Jan 1, 2008

By Zhang P, Wang T, Duan X, Sheng T, Kong L, Wang Y

This paper puts forward an artificial neural network (ANN) for the forecast of deformation of the surrounding rock deformation. On the basis of this, this paper gives some examples of its application. The results show that the ANN model has a high forecast accuracy.

Jan 1, 1995

By Y V. Haarlem, P Coghill, N G. Cutmore, M Millen, I Carter

Due to the low concentration of gold, ore sorting for gold has always required measuring indirect properties, such as density or colour, to allow separation on a rock by rock basis. This only works on an ad hoc, by deposit basis and is likely to be least reliable where it is most required in low grade ores. One candidate technique, Gamma Activation Analysis (GAA) has been demonstrated to directly measure gold extremely accurately in powder samples of around 500gm and is used in the Chrysos PhotonAssay assay system. This method uses a linear accelerator (linac) to generate the X-ray radiation that activates the ore at low levels to emit a characteristic gold gamma ray that is then measured by a radiation detector. CSIRO is adapting this measurement technique to application on a belt at up to 800tph to measure pods of ore. The principal differences between measuring samples and an on-line measurement of pods are the requirement to measure coarse ore (<50mm), to measure a larger volume of ore as uniformly as possible, and to have an open-ended geometry with adequate shielding of the linac radiation source. These issues have all been addressed with measurements of coarse ore reported down to around 1ppm in sub-optimal test conditions. They have been demonstrated for <75mm particles with detectors capable of measuring a large volume geometry continuously. These are projected to allow measurements down to 0.3ppm in more optimum conditions for a 10 second measurement time period where the U/Th content of the ore is less than ~10ppm. Extensive Monte Carlo modelling has demonstrated that adequate shielding can be provided in relatively simple geometries with only 1 right angle transfer in the material handling. Steady progress is being made to reach the technical position required to trial an ore sorting system.

Nov 10, 2020

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

By P C. J Blackney, I M. Glacken

Spotted Quoll is a massive sulfide nickel deposit located in the Forrestania greenstone belt in the Archaean Yilgarn block in Western Australia. Discovered in October 2007, mining has progressed from open pit to underground and currently uses longhole open stoping with paste fill as the primary stoping method. Immediately prior to 2019, the Mineral Resource estimate (MRE) was defined by a single grade domain of nickel greater than or equal to 0.8 per cent, irrespective of the host lithology, a legacy of the original ore wireframe being built using explicit methods. While a number of obvious structural offsets were honoured in this nickel grade domain, only one modelled fault was used to undertake domaining of arsenic. From 2019 onwards, implicit modelling in Leapfrog Geo™ was used to construct a mine-scale geological model, which triggered the definition of a high-grade core of massive/matrix nickel sulfides surrounded by a low-grade halo of stringer/disseminated nickel sulfides in the surrounding rock. As part of the evolution of the geological model and with the aid of Seequent Central™ to allow collaboration between site-based mine geologists, Perth-based resource geologists and Melbourne-based consultants, a detailed review of the structural mapping was carried out as additional information from underground development became available. This allowed numerous faults and shears to be identified – particularly in the lower half of the mine. These were used to define further structural domains and to refine the understanding of the nickel and arsenic grade distributions in the mineralised envelope. The increased definition to the domains provided by the geological model resulted in a significant improvement in the accuracy of the Mineral Resource estimate, as measured by reconciliation using voids of the mined stopes determined from the cavity monitoring survey (CMS).

Mar 22, 2022

Waihi Gold Mining Company Limited, a wholly owned subsidiary of Normandy Mining Limited, operates the Martha gold mine, located in the township of Waihi, New Zealand. The operation, an unincorporated joint venture, comprises Normandy Mining Limited (67.070/0) and Otter Gold Mines (32.94%). Since gold was first discovered at Waihi in 1878, it has formed a key part of the region&apos;s economy. In 1909 the Waihi mine was described in a report to Parliament as æthe most important gold mine in Australasia and one of the greatest in the world.Æ That was a record year for production, with 416,813 tons of ore mined and some 1,120 men employed. Today the mine produces up to 1,250,000 tonnes of ore annually, and the project employs some 234 men and women. In 1999 the value of the gold and silver produced ($59 million) made up 47% of Waihi&apos;s estimated GDP. Waihi Gold has made significant contributions to the Waihi economy, community and the Hauraki region as a whole. Since the mine was re-opened in 1987, thousands of local people have benefited from the mine. In 1999, consents were granted allowing an extension to the mine life (the Extended Project) and this will result in a further seven years of economic benefits resulting from mining activity. The Company has undertaken extensive consultation throughout project planning, construction, operations and rehabilitation. Ongoing liaison and involvement with all community sectors, including Tangata Whenua and Iwi, local residents, recreational groups and schools remains an integral part of the operation. Throughout the life of the modern Martha Mine, the Company has actively supported the local community in the form of donations, sponsorships, the provision of amenities, and by participating in community events. A well established environmental team exists at the site. Environmental and community performance is measured by an independent five-assessment process, and the Company is committed to achieving excellence through ongoing improvement programmes and staff awareness. When the mine is closed, the open pit area will be transformed into a recreational lake, and the tailings storage facilities will be rehabilitated to become a combination of wetlands, grassed areas and ponds. Resources will be provided by the Mine to ensure the rehabilitated site remains in a safe and self-sustaining, stable condition in perpetuity. The mine is regarded as a showcase on a world standard of how a modem mining operation can successfully coexist with the nearby community.

Jan 1, 2000

By M I. Roberts

As Australia’s mining industry painfully retrenches, mining executives and managers strive to remain viable by seeking significant productivity increases directly through process improvement and indirectly by improving leadership and workplace culture, the most powerful determinant of productivity. Culture is the combination of people’s attitudes and behaviour, together with leadership values and focus.Comprehensive new and automated data collection and management systems promise much for improving productivity, yet despite rapid advances in measurement and sharing of data, the use of data can reduce productivity unless behavioural aspects are considered and designed as part of implementation. This is because systems drive behaviour that in turn shapes attitudes to determine culture.Experience from many mine sites and other industries in three countries confirm that the most powerful drivers of people’s behaviour are the Measurement-Analysis-Reporting system and business leadership.This paper discusses fundamentals of practical, statistically valid process measurement, analysis and reporting systems before discussing associated leadership considerations for sustained improvement in safety, productivity, employee retention, leadership, accountability and commercial returns.The key to productivity improvement is improving core processes and important support processes. In turn, the key to process improvement is identifying the major process components and their interaction by measuring and then analysing their variation and level of performance. Understanding variation is often neglected yet is usually highly significant. It is essential that the fundamentals of statistically valid yet practical process and data analysis are understood and incorporated into system design to ensure productive, informed behaviour.The design and use of Measurement-Analysis-Reporting systems influences behaviour most profoundly and determines people’s effectiveness. Behavioural aspects are detailed by focusing on six primary drivers of human behaviour and five basic systems for managing businesses. These are integrated in a seven-step process and productivity improvement methodology that combines statistical, analytical, systems and behavioural factors.The paper includes development, implementation and tracking of a project plan for improving management and leadership systems to drive aligned behaviours. This key leadership responsibility is essential for improving performance to get the most from capital while providing people with the opportunity to develop greater autonomy, which is essential for self-discipline, responsibility, initiative and accountability.CITATION:Roberts, M I, 2015. Integrating measurement, systems and leadership to build safe, productive cultures, in Proceedings Third International Future Mining Conference, pp 73–82 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By S Bourke, R Stone, B Hill

Since Jameson Cell flotation technology was first installed in a coal flotation application in 1988/89 at Newlands Coal Handling and Preparation Plant (CHPP) there have been fundamental improvements to its design which has led to its current status as the leading technology in Australia for fine coal flotation. These improvements, which include key hardware modifications, consist of the re-development of the orifice plate to produce considerable increase in wear life and reduction in power consumption for a given air entrainment and a significant increase in the amount of air that is entrained. Modifications to the downcomer allow maximisation of residence time and air entrainment while changes to the feed and air distribution system allows a reduction in installation cost and a reduction of solids ingress into the air line. Additionally, operational improvements such as the use of recycle to maintain constant flow to the cell feed are discussed. The recent installation at Hail Creek in the Bowen Basin, which consists of three B6000/20 Jameson Cells (6 m diameter bottom-fed distributor with 20 downcomers) will be reviewed as a case study. The latest design and operability of the cells are summarised and compared against one of the original designs at Riverside CHPP also in the Bowen Basin.

Jan 1, 2005

By J Santana, V Ferraz, G Pinto, G Cruzado

Morro Agudo is an underground zinc and lead mine owned by Nexa Resources. The mine uses room and pillar as the main mining method. The recovery of pillars as well as the opening of new excavations using sublevel stoping as mining method has been studied. On some occasions, the need to recover pillars and open a stope by using the sublevel method happens in a region that is already excavated or in deeper areas than those mined so far. These changes represent a major geotechnical challenge due to the complex openings of the mine and interaction between two different mining methods. Historically, geotechnical mapping, kinematic analysis and a 2D numerical model were used to evaluate the new mine openings, and in 2021, 3D numerical model was introduced, which enabled global and local assessment of new excavations impact and the stability of openings after recoveries. The 3D model, made with MAP3D, is used to evaluate each pillar to be recovered, considering the spans of the resulting openings, the ideal sequencing of removal to maintain stability, in addition to the impact and geometry of the pillars left in the chambers. Pillar recoveries done in 2021 and the impact of it on the pillars left were the sources of the back analysis to calibrate parameters inputted on numerical model to assess recovery on new chambers and Phyllite has been considered into the model and it has been a source of instability due to its parallel position to roof of room and pillars and stope hanging walls.

Nov 29, 2022

By J J. Jiang, B G. Bow

Atlas Iron Limited’s (Atlas) Abydos Mine has developed its Scarborough open pit proximal to a rock shelter that has been assessed as a significant Aboriginal heritage site by the Traditional Owners of the land. The rock shelter, named Yurlu Kankala, is located to the north-west of the pit with a stand-off distance of 35 m. Within Atlas’ Native Title Agreement with the Traditional Owners, and approvals from the Western Australian Department of Aboriginal Affairs, commitments have been made to conduct mining in a way that avoids or at least minimises disturbance and damage to the rock shelter. This complies with the Aboriginal Heritage Act 1972 (WA) and respects the heritage and culture of the Traditional Owners.CITATION:Bow, B G and Jiang, J J, 2018. Iron ore mining in proximity to a significant Aboriginal heritage rock shelter, Pilbara Region, Western Australia, in Proceedings Life-of-Mine 2018, pp 2–5 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By M Bettison, R Marton, R Wright, M Lowry

Depending on the geological setting, waste rock from mining can present risks to achieving acceptable closure outcomes. In the Pilbara iron ore mines, the majority of waste rock is geochemically inert. However, small percentages of pyritic material with the potential to generate acid and metalliferous drainage (AMD) require considered management within mine waste stockpiles designed to minimise AMD release to the environment. A larger percentage of waste rock has physical characteristics (e.g. erodibility) that may impact upon long-term landform stability. CITATION:Marton, R, Wright, R, Lowry, M and Bettison, M, 2018. The golden thread of waste characterisation from exploration drilling to waste rock placement, in Proceedings Life-of-Mine 2018, pp 90–92 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By M L, G Maddocks, A Ferrier, ers, A Forbes

Evolution’s Mount Rawdon Operation (MRO) produces gold and silver through open pit mining methods. The mining operations are scheduled to be completed in FY24 (Financial Year 2024), after which low-grade stockpiles will be processed until the end of FY27. As part of MRO’s Progressive Rehabilitation and Closure Plan (PRCP), RGS Environmental Consultants (RGS) and Deswik were engaged to develop the final landform surface and a whole of site probabilistic water balance/water quality (WB/WQ) model to evaluate the viability of several closure options with respect to water quality in the various site water storages, particularly the final void which will form a pit lake. This case study details the closure option which included (amongst other things) covering the final landforms and directing water toward or away from the final void post closure. Closure and rehabilitation for MRO had previously been planned and evaluated on a ‘domain’ basis. Furthermore, the rehabilitation plans and final water management plans for the Tailings Storage Facility (TSF), Waste Rock Storage Facility (WRSF) and other domains were not coordinated, possibly resulting in competitive rehabilitation material requirements at the commencement of closure activities. An assumption was that a legacy non-acid forming (NAF) stockpile would provide sufficient material to both supplement ex-pit material for the construction of the TSF embankment raises and to complete all closure activities, but the volumes available and the volumes required to complete the closure activities had not been quantified.

Aug 2, 2023

By K Clode, J Al-Shdifat, S Daykin

Planning for a circular economy allows for previously untapped market opportunities to be explored, resulting in new, innovative revenue generating opportunities, while also reducing environmental impacts. In particular, rare earth elements (REE) are in rising demand as they are key components of over 200 products across a wide range of applications (Xie et al, 2023) including renewable energy technologies. There is a geographical disparity in deposits, with China being the top producer, generating 70 per cent of global production in 2022 (Laboure, 2023). This single dominating source has created supply chain concentration and hence supply risks for other nations, providing a driver for finding alternative sources, such as mine-influenced water (MIW) and tailings. In this study, Isle presents a robust due diligence methodology for undertaking a global horizon scan into REE recovery technology, for a large mining company, from tailings decant water on a specific site. Previous studies of the tailings decant water at this site had shown potentially significant concentrations of both heavy and light REE, but challenges such as high flow, very low pH and high concentrations of iron had previously made recovery unfeasible. Due to these challenges, the horizon scan focused on technologies that had the potential for selective recovery, despite the challenges with water quality, and considered a range of Technology Readiness Levels (TRLs). This included an adsorption-based process that has the potential to selectively separate individual REE, and a polymer based selective flocculation technology.

Sep 1, 2024

By B P. Voutharoj, R A. Dutch, M Paknezhad, T Ostersen

With the proliferation of new sensor technologies, acquiring multiple data sets over the same ground is becoming cheaper and easier than ever. This new, higher resolution multivariate data provides a significant resource for exploration and resource geologists but comes with the added complexity of effectively integrating the various data sets in useful and meaningful ways to elucidate new geological understanding. Both geophysical data sets and hyperspectral data are extensively used for exploration targeting, providing different information at different resolutions and crustal scales. One of the biggest challenges comes from trying to effectively integrate data sets that record very different physical properties, across the different scales these data are captured at, in a way which can allow for a data-driven analysis of these combined data sets.

Sep 1, 2024

By A G. Guinea

If you were reading this article in a newspaper or similar in the 1800s, you would know that the world was firmly in the grip of the Industrial Revolution. You might have been one of the families that decided that an agriculturally based existence was no longer for you, and that the promise of a factory job was more appealing and more secure. And it was. Financially at least. Not so much from a workplace safety perspective.

May 5, 2022