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By Myers PA, Noble MR, Lawrence JS, Cannings WR

The Perseverance orebody presents the Agnew Mine with a wide variety of geological settings, necessitating the application of several mining methods within the limited strike length being extracted.Mining methods have been introduced and modified during the six years' production history of the property and that evolutionary process remains very active.The methods used, in use or planned, are:Hand held scraper cut and fill Hand held mechanical cut and fill Post pillar cut and fillOpen Stoping (uphole benching) Modified vertical crater retreat Sub-level caving

Jan 1, 1985

By N Clarke, J Hunt, A Barros, N Guerrero, L Keeney

Grade Engineering® (GE) involves a range of integrated technologies and operating protocols for improving effective feed grade through early rejection of low value material prior to costly processing activities and has the potential to transform the economics of large, low grade, mining operations. Extensive GE test work by AngloGold Ashanti (AGA) and the Cooperative Resource Centre for Optimising Resource Extraction (CRCORE) determined that the Gramalote gold deposit in Colombia is highly amenable to implementation of grade-by-size screening to upgrade the ore at a production scale. To understand the relationships between geology and the upgrade response drill core and bulk samples were analysed at the Centre for Ore Deposit and Earth Sciences (CODES) as part of a larger CRCORE project to understand geological controls on grade-by-size deportment, i.e., the tendency for specific mineral phases to preferentially fractionate during breakage into different size fractions. This work is focussed on understanding the role of mineralogy and texture in influencing rock breakage and natural fractionation at a range of scales. Detailed logging of Gramalote drill core and mineralogical analyses including hyperspectral logging, portable and bench-scale X-ray fluorescence (XRF), plus low resolution Laser Ablation of intact drill core pieces, combined with data from site (drill logs, geochemistry, petrophysics) were used to evaluate the ore and alteration mineralogy, vein paragenesis and textural variability. This provided information on gold deportment and allowed the identification of favourable host veins. Bulk sample material from different ore grade zones was also analysed. A comparison with the results of GE testing shows that positive upgrade results are produced by rocks with abundant veins, particularly those associated with potassic and/or white mica alteration. This work indicates upgrade response can be predicted from drill core using data collected by a combination of automated systems including hyperspectral data, XRF, and detailed drill core logging.

Nov 10, 2020

By R Young

Independent Project Analysis (IPA) is in the business of benchmarking the performance of capital projects on behalf of owner companies in the processing and extractive industries. IPA assesses between 500 and 800 projects each year. The projects are conducted globally and range in size from about $1 million to over $30 billion. Using the data, we are able to benchmark the performance of Australian projects against the rest of the world. This presentation focuses on the performance of large (greater than $100 million) projects that involve chemical or thermal processing.We regularly hear calls for more processing to be conducted in Australia but on the other hand industry leaders are concerned about the poor success rate of solids processing projects in Australia. Data gathered by IPA indicates that there is good reason for the concern. Out of a sample of 31 large processing projects conducted in Australia, 23, or 74 percent, were classed as failures. This performance is significantly worse than for similar projects in other parts of the world. The presentation analyses why the performance is worse and demonstrates that many of the reasons behind the failures were manageable by the project team. Furthermore, members of the project teams on at least half the failed projects knew that the projects were on a path to failure before the project was authorised but could not be heard.The presentation discusses how large projects that involve process design and, in many cases, new technology, need to be set up for success. *This is an abstract only. No paper was prepared for this abstract.*

Aug 8, 2011

By J D. Illescas, S N. Arnold, D R. Shaw

Ion exchange (IX) as a primary production technique has been applied commercially since the 1950s; its application in the uranium industry continues to be widespread and is utilised to a lesser degree in the gold industry. The majority of ion exchange applications, outside of gold and uranium, have primarily been for secondary metal recovery and impurity removal. Newer developments in the application of ion exchange, as well as changes in regulatory requirements, are bringing about the wider use of ion exchange as a primary production technique not only for high value metals such as uranium, platinum group metals (PGM), refractory metals and rare earths, but also looking at base metals such as nickel and copper. The ability to build lower-cost, safer, less polluting processing plants with smaller footprints is driving a greater interest in IX, with the main competitors remaining solvent extraction and carbon-in-pulp/leach. This paper discusses a number of areas where IX has been applied and its advantages compared with other techniques.CITATION:Shaw, D R, Arnold, S N and Illescas, J D, 2012. Ion exchange in hydrometallurgy - Secondary metal removal or primary production technique?, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 17-22 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By K G. van den Boogaart, U Mueller

"An accurate prediction of benefit for some types of ore may require not just the ore grade, but a whole compositional characterisation of the estimates; that is, its full mineral composition including waste composition and nuisance elements. An example is Nickel laterite ores, where Ni/Co content must be complemented by estimates of many other elements, as these might have a notable impact on ore processing.Estimates are often obtained with (co-)kriging or co-simulation; however, geostatistics applied to compositional data may yield spurious and inconsistent results because of the constant sum constraint. The log-ratio approach avoids such problems. It proposes a three-step procedure: data are mapped to a set of log ratios of components; for example, the additive log-ratio transformation (alr) transformed scores are modelled with an appropriate fully multivariate geostatistical toolbox; for example, direct/cross-semivariograms and co-kriging or co-simulation results are back-transformed to the original units.Some practical aspects may make the application of this technique difficult: the assumption of Gaussianity and the high dimensionality of the compositions combined with the need for using multivariate methods. This contribution compares several ways of treating compositional data (combining normal score transformation, log-ratio transformations, and minimum/maximum autocorrelation factor (MAF) decomposition) with respect to their ability to generate sensible simulations. The various approaches considered are illustrated with a Nickel laterite data set for which ten variables are available. Both theoretical considerations and illustration results suggest that the best combination is (log)ratio-normal score transform-MAF, in this order. The factors so obtained are closer to Gaussian, approximately spatially decorrelated and can be simulated independently. Simulations can later be recombined to alr-simulations, which in turn may be converted back to point compositions. The resulting simulated compositions are compared with a full Gaussian co-simulation of the raw data. The log-ratio methods show reasonable to good reproduction of mean values, and distribution of the data set and by construction satisfy the total sum constraint, in contrast to the simulations based on raw data for which the total sums fluctuate strongly.CITATION:Mueller, U, Tolosana-Delgado, R and van den Boogaart, K G, 2014. Approaches to the simulation of compositional data – a nickel-laterite comparative case study, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014, pp 61–72 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 24, 2014

By Harvey T, Kizil M, Bride J

Hydrogen sulphide (H2S) as a seam gas has occurred in several locations in the German Creek seam at Southern Colliery. This paper overviews the techniques developed to quantify the H2S content of the seam, overviews research into controlling and reducing H2S emissions from the seam, and details the procedures used to mine through the HZS zone in 702 longwall panel. Learning points from research and mining experience are reviewed for application in the next longwall block.

Jan 1, 1998

By Kasai H, Hibi T, Matsuishi S

Coal oil mixture (COM), a liquid fuel pro- duced by mixing together coal and heavy oil on the 50-50 basis, has been brought to a level of practical use in Japan, being actually employed by a oil fired system at Yokosuka Thermal Power Station of The Tokyo Electric Power Co., Inc. A COM Production Plant, built in Onahama which is located about 160 miles from Yokosuka, required COM to be transported by sea. Mitsubishi Heavy Industries, Ltd. therefore performed a series of studies to develop a spe- cialized COM carrier, the world's first of its kind. Long lasting high stability is of pri- mary importance to successful use of COM. Much have been done in the way of research on stability of COM in the static storage, and the mechanism of COM static: stability is almost completety known. On the other hand, the knowledge about the COM dynamic stability, such as the stability while being transported aboard the COM carrier at sea, is still limited at the moment. The motion of COM aboard the COM carrier and how COM would settle were studied by tests. A visualization test on the COM behavior under dynamic motion was also performed and the mechanism of COM dynamic stability was analysed. The tests showed that the ship rolling motion had @n effect of promoting the settling of coal content of COM in the cargo hold. And studies were also made to device a method for esti- mating the settling quantity of coal during sea Transportation.

Jan 1, 1987

Ore textures in Australian BIF-derived ores are quite complex and have formed the basis for ore genesis models, which includes hypogene upgrading or supergene upgrading then regional metamorphism for the microplaty hematite ores and supergene upgrading for the martite-goethite ores. Despite a high level of ore texture knowledge, little is known about the spatial distribution of ore textures within deposits or their relationship to downstream processing. This paper describes a new iron ore texture classification system to better understand the vertical textural zonation characteristics of Australian BIF-derived deposits, the interpreted role of recent supergene upgrading processes on modifying primary ore textures and their implications for downstream mineral processing. The iron ore textural classification scheme presented uses textural groupings defined on the basis of similarities in mineralogy, ore texture, porosity, mineral associations and hardness. The scheme is non-genetic and has been successfully applied to deposits in the Pilbara, Yilgarn and Gawler cratons. The main ore texture groups include dense martite/hematite, microplaty hematite, microplaty hematite-goethite, martite-goethite, goethite-martite and goethite-rich. Each group can be further subdivided into physically hard to softer subcategories. The ore textural groups can be divided into those interpreted to be associated with primary replacement of BIF and secondary textures resulting from more recent modification by near-surface hydration or dehydration processes. A schematic vertical section through BIF-derived deposits consists (from surface) of detritals underlain by a carapace, both of which may have been eroded, followed by a hydrated zone with replacement of primary ore martite and microplaty hematite by vitreous goethite. The hydrated zone is underlain by 0.2 - 6 m thick zones of intense dehydration and textural infilling of porosity with hematite and hydrohematite. Immediately below the dehydration zone is a strong zone of leaching, where more porous and friable ore textures occur, followed underneath by a gradational contact with primary ore. Secondary supergene processes can impact on beneficiation with hydration and leaching resulting in more difficult density separations at the concentrator stage due to reductions in density differences between ore and gangue and loss of heavy media into pores. Supergene modification of primary BIF-derived ore textures can substantially change lump metallurgical properties, with hydration and dehydration favourably increasing lump yield but reducing resistance to thermal shock whilst leaching will give the opposing outcome. The lump properties of ore textural groups appear to be relatively consistent within and between the iron ore deposits examined.

Jan 1, 2002

The initiation of cast Pentolite primers by detonating cord has been examined by the combination of two different experimental techniques with computer simulation by the finite element hydrodynamic code DYNA2D. In the first type of experiment, the cord/primer system was placed in a water aquarium, and photographed using a high-speed image converter camera. This highlighted the emergence of the detonation front through the primer surface and the generation of shock waves in the surround- ings. Numerical simulation was used to interpret the experimental record, establishing where the cord had induced buildup to detonation inside the primer. The second experiment used the plate dent test, where the primer was placed in contact with a block of metal (here aluminium), with the resul- tant dent in the metal surface being a measure of primer output. Detailed numerical simulation of this test confirmed that the observed dent was caused by the development of a complex series of shock waves inside the Primer.

Jan 1, 1988

By P W. Cleary, G K. Robinson, M D. Sinnott

Discrete element modelling (DEM) is a research tool that involves numerically solving the equations of motion of large numbers of particles. It can be very useful for investigating mechanisms that can lead to bias when extracting samples from material as it is carried on a conveyor belt or as it falls from the end of a conveyor belt. DEM is more realistic than conceptual models and mathematical models; but it is not as realistic as physical experimentation. Its primary advantages over physical experimentation are that it is cheaper and that it allows many factors to be varied while keeping other factors unchanged.This paper reviews our investigations of the performance of sampling systems by using DEM. The sampling systems investigated include falling-stream cutters, cross-belt cutters, Vezins and a device called a ætrue-beltÆ cutter, which is being developed. The purpose of the review is to explain what DEM has contributed to the theory and practice of sampling, and to indicate what it is likely to be able to contribute in the future.CITATION:Robinson, G K, Cleary, P W and Sinnott, M D, 2012. How discrete element modelling is influencing the theory and practice of sampling, in Proceedings Sampling 2012 , pp 15-20 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

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 N Jamson, T K. Rohde

The Mine is an underground zinc (Zn), lead (Pb) and silver (Ag) operation in central New South Wales (NSW). Broadly speaking the Mine has two domains that require rehabilitation, the mine industrial area (MIA) and the tailings storage facility (TSF). The MIA has been used for the handling and processing of ore and contains elevated sulfate, sulfide and metals (Pb, Zn). The TSF receives the by-products of processing, that is, potentially acid forming (PAF) tailings which also contain elevate sulfate, sulfide and metals. Typically, the rehabilitation of a TSF involves two controls. Firstly, controlling the potential for PAF tailings to form acid rock drainage (ARD) by limiting interaction with oxygen. Secondly, once the tailings are unsaturated, limiting interaction with water (usually as rainfall) to reduce the potential for ARD to be transported to the receiving environment. These two controls are often employed in the form of a cover.In semi-arid environments there are many Australian examples of covers that have been built to limit interactions of mine by-products with oxygen and water. Typically, the covers contain one or more layers and are built from soil and rock which may include run-of-mine rock. The Mine however has limited supplies of stockpiled soil; and run-of-mine rock is not generated in large volumes because it is used as backfill underground. A cover design strategy was developed to cater for these limiting factors. The strategy identified soil, ore and rock accretion (the accretion) below the MIA could be a potential source of borrow material for the cover. The purpose of this paper is to describe the cover design process, the method and results of large (2 m tall) column trials that were used as a cost-effective way to trial three cover options and finally, the paper describes the water balance that was developed from the column trial results and subsequent modelling using SVFlux.CITATION:Rohde, T K and Jamson, N, 2018. Making use of potentially contaminating mine waste in cover design, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 285–298 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By van der Walt TJ, van Deventer JSJ, Reuter MA

Owing to their complexity, many metallurgical processes are difficult to model fundamentally, and as a result more attention has been focused on the use of artificial intelligence techniques to simulate these processes. In this paper recent advances in the use of neural nets to model processes not amenable to conventional methods are discussed. These include the application of a new modelling methodology based on the use of neural nets for the dynamic simulation of metallurgical processes, the use of conventional techniques in conjunction with neural nets to simulate gravity separation circuits, as well as the detection of gross errors in variable measurements by means of a neural net representation of the relation between measurement and constraint residuals.

Jan 1, 1993

By R Berry, J Lett, C L. Harraden

"In the past decade, increased processing capacity combined with precision robotics in high resolution spectrometers has resulted in a new generation of high-speed hyperspectral core logging systems. The application of these multisensor automated platforms provides a key advancement in the characterisation of metal resources. The development of this technology has allowed for comprehensive, drill core-based, mine-scale rock mass characterisation studies. Here we propose a new method for the extraction of parameters that seek to more accurately quantify ground conditions, including quantified rock mass rating (RMR) and the Rock Tunnelling Quality (Q) Index. Data inputs include rock quality designation (RQD), number of joint sets, joint roughness, joint alteration and joint spacing. Geologists and geotechnical engineers have historically collected these inputs by manually logging drill core. With automated core scanning technologies, these parameters can be estimated from the acquired image data and used to objectively calculate RMR and Q-index values for oriented core.Corescan is an automated hyperspectral core scanner that uses a 3D laser profiling system to measure the height of the surface of drill core. This technology allows for rapid core analysis to produce detailed fracture and rock condition data. Through an integrated geometallurgical approach, the proposed methodology will test the accuracy of joint measurement using the height profile Corescan data from oriented drill core. This will be combined with joint roughness and alteration mineralogy measured from the hyperspectral images to calculate the RMR and the Q-index continuously downhole. The values obtained can then be compared to the traditional, manual geotechnical log data. If the precision is sufficient, these techniques can then be applied site-wide to automate the collection and modelling of key ground condition classification indices across an entire deposit. Compared to the laborious manual geotechnical logging procedures that currently form the industry standard, utilisation of core laser profile data and high resolution red-green-blue (RGB) images provide an opportunity to collect large volumes of consistent geotechnical data, which can increase the efficiency and accuracy of deposit scale geotechnical models.CITATION:Harraden, C L, Berry, R and Lett, J, 2016. Proposed Methodology for Utilising Automated Core Logging Technology to Extract Geotechnical Index Parameters, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 119–124 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

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 J Pan, G Qiu

In this paper, an analysis is made of the present situation in the Chinese steel industry and its demand for iron ores. It is shown that the demand for iron ores has been growing substantially with the rapid development of the steel industry all over the world, especially in China. However, the iron ore market is currently in the situation where supply exceeds demand due to the economic crisis, with more investment in mines and less output of steel for several years ahead all over the world. Gigantic pressure is confronting the Chinese steel mills due to the too high and irrational price of iron ores. It is time to return the price of iron ores to a normal position much closer to their value. More attention has therefore been paid to developing low-grade and complex iron ore resources in China due to the irrational price of imported iron ores. More innovative mineral processing processes have been developed to tackle these complex resources. A systematic introduction to the development of beneficiation processes for low-grade iron ores is provided, including upgrading low-grade siderite, limonite, micron sized haematite and magnetite resources.

Jan 1, 2009

By D Manhire, G Hogan, M Ryan, S Whiteley

Site restoration at the L&M Mining Limited alluvial gold mining project at Waikaka near Gore, Southland is described. In 2000 mining operations started to recover alluvial gold beneath historical dredge tailings over 244 hectares in the flood plain of the Waikaka Stream. The project had an eight to nine year mine life but was prematurely closed in 2002 because of economic considerations. Restoration of the site back to pastoral farming, with shelter-belt and amenity tree, shrub, and wetland plantings is described. Dealings with the landowners and regulating authorities are addressed in the paper.

Jan 1, 2003

By M Frenzel

At the last MassMin Conference in Sudbury, Caterpillar’s vision of a continuous mining concept for block caving operations was presented on the background of global raw material demand and its continuous increase. By analysing today’s structure of mining processes in block caving, the paper (Krings, Steinberg and Frenzel, 2012) highlighted the main bottlenecks in the process chain and identified conceptual solutions by help of a case study. The main focus was the paradigm shift from discontinuous batch type operation to a continuous mining process of the blocks.In 2016, the strategic vision has taken major strides forwards and remote continuous operation has become a reality. Caterpillar’s continuous operation system – the Rock Flow system – was successfully installed in Codelco’s Andina mine and start of operation is scheduled in the first half of 2016.Based on continuous product developments, this paper sets the focus on two main aspects of continuous mining. First, field experiences of the Rock Flow system will be shared, highlighting the Andina project course from system installation, to commissioning and successful system start. The second aspect concentrates on the system and mine layout as discussed in the case study scenario in MassMin 2012 (Krings, Steinberg and Frenzel, 2012).Based on Caterpillar`s continuous product development, the Rock Flow system set-up and panel design were modified for a general roadway design and drawpoint layout. The new design allows an optimised use in block preparation phase (spreading) and full production phase (reaping), operating a fleet of load-haul-dumps (LHDs) and Rock Flow systems. The combined use of the two technologies optimises the mining process in every stage of block life and significantly increases the performance of the continuous block caving operation in the production panel to pave the road for the next generation of super caves.CITATION:Frenzel, M, 2016. New continuous production system in block cave mining – the rock flow system, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 543–548 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By S Garnes, W Austerberry, S Fraser

Despite significant investment in safety in the mining industry (mostly focused on processes and systems), many companies are unable to sustain and further improve their performance resulting in continued workplace incidents. The problem persists despite the best efforts of companies and allocation of resources to achieve Zero Harm. A DSS survey in 2019 found that two out of five companies that cannot manage risks and face disaster, leave the market within five years. All safety/risk management systems have the common steps of risk identification, prioritisation, design of controls consistent with risk tolerance, and verification of implementation/operability of controls. This is then complimented with improvement to one or more of the above elements through learnings obtained from incident investigations. In principle, the above process should work to reduce risks to, and keeping them at, a risk level consistent with risk tolerance in the organisation.

May 5, 2022

By P Yß±ez, G Ferguson

The El Teniente mine produces more than 340 000 tonnes of fine copper per year from an industrial complex of underground mine, concentrator and smelter. Mass caving methods are employed to deliver approximately 95 000 tpd of ore to the mill, from a number of sectors underground, each sector being in effect a large-scale mine in its own right. This mining activity has faced challenges over the course of the last century such as:the capacity of the underground mine has been expanded to maintain and increase output of fine copper; the increasing size of the ore fragmentation forced to change the mining method to achieve the high productivity and profitability required in the business; and to modify the mining methods to continue mining at depth with safety. Fundamental activities in these mining methods, for the successful initiation of caving and subsequent draw, are:undercutting the base of the block or panel by blasting; and excavating of drawbells. The undercutting design evolves mainly on the height of the blasting to manage the change on ore fragmentation. The methodology move away from incorporating massive areas, typical of the block caving method, to a continuos blasting, typical of the panel caving method. Drawbell design changes on geometry, dimensions and sequence of excavation to deal with a corse ore fragmentation and the resolution of mining difficulties in the form of major rock bursts and collapses of production facilities. This paper focuses upon the evolution of the undercutting and drawbell design used at El Teniente mine and techniques under consideration to deal with future caving operations to provide the bulk of the daily production for the foreseeable future.

Jan 1, 2000