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In the estimation of reserves the known values of the variables of interest from surrounding drill holes are used to compute or estimate the unknown value of the orebody over a given region or at a given point of interest. The classical means of doing this are: 1. The Polygonal Method û where the region is divided into polygons centred on bore holes, each variable is then assumed to have constant value over each polygon. 2. Inverse distance methods, where the variable is assumed to vary linearly with the distance between the known values of the drill holes. 3. Inverse distance squared method û a quadratic variation is assumed for the variables between the bore holes.

Jan 1, 1983

Study on Oil Agglomeration Flotation for Deinking

Sep 13, 2010

By L D. Munro, S A. Jackson

This paper provides a logical approach to developing a TSF design concept through: • Identifying key properties of tailings and containment structures; • Reviewing underlying principles for effective operation; • Showing how these apply to select an appropriate TMS; and • Demonstrating how to align the TMS to site-specific constraints and TSF design. This approach follows a path of rigorous data analysis independent of discharge parameters (whether low-density slurry, paste or cake disposal) to select the most cost-effective and sustainable approach for any given material or site.

Jul 1, 2021

Study of Bauxite Separation by Using Flotation Column

Sep 13, 2010

Study on New Tungsten Beneficiation Technological Flow Sheet of Shizhuyuan Polymetallic Mine

Sep 13, 2010

By J K. Claflin, S R. La Brooy, A M. Claflin

Rotary kilns have been in service in the gold industry to regenerate carbon for 65 years. At the time oxide ores with gold head grades of 8 to 10 g/t were being treated. Carbon could be regenerated adequately at 650°C and solution losses were less than 1%. Forty years ago, research indicated that heavily fouled carbon from flotation circuits had to be held at 750 to 850°C for ten to twenty minutes for full reactivation (Avraamides and La Brooy, 1987), gold head grades were typically 5 g/t and solution losses typically 0.02 ppm – still less than 1%. In 2017 it was determined (Claflin et al., 2017) that a residence time of less than 1 minute at 750°C can be adequate to reactivate carbon fouled with organics sufficiently to achieve 0.005 ppm solution losses in a flotation tailings leach plant.With the potential for discovery head grades to drop below 0.6 g/t, solution losses of 0.02 ppm represent over 3% loss. Tight operation of the whole carbon circuit is required to keep gold solution losses below 1% going forward.There are alternatives to a rotary carbon kiln, e.g. vertical kilns of which the Minfurn, Rintoul and Combustion Air kilns are examples. The alternative kilns can be heated using electrical heating elements, induction, and microwave. These kilns can operate successfully under the right conditions, however, they are almost exclusively for small carbon throughputs and are not suitable for the large carbon advance rates that are required to process low head grade ore deposits. Large throughput carbon kilns are are almost exclusively fossil fuel fired rotary kilns and the subject of this paper. In the view of the principal author, a fossil fuel fired vertical carbon kiln is preferred to a rotary kiln, however, it is not currently used in the industry.Thermal regeneration of activated carbon has a major impact on gold recovery in the carbon circuit. The carbon kiln and associated equipment constitute 3 to 5% of the capital cost for an oxide processing plant and up to 10% of the capital cost if flotation tails are leached. Despite the capital cost and impact on recovery, the carbon kiln is often poorly selected, operated and maintained.Six years ago Ausenco embarked on the Carbon Kiln Initiative to reduce solution gold losses. This body of knowledge has been published in a series of papers culminating in this paper on how to:1. Select a kiln appropriate for the flowsheet;2. Maintain the kiln to achieve design operation; and3. Operate the kiln to minimise costs and maximise reactivation.CITATION:Claflin, J K, La Brooy, S R and Claflin, A M, 2018. Carbon kiln selection, operation and maintenance, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 251–274 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By Stanojevic R, McGlinn PJ, Day RA, Levins DM

This paper reports the results of a number of studies that Ansto has carried out for mineral sands companies concerned about low-levels of naturally-occurring radioactivity in their products. Where measured levels of radioactivity have exceeded allowable levels, Ansto has used specialised techniques to identify the source and distribution of the radioactivity and investigated processing strategies to remove the Contamination.

Jan 1, 1993

Project developent proceeds by increasingly detailed studies addressing overall project returns through an analysis of the substance, risks and costs associated with the following elements: ò Reserves ò Mining ò Processing ò Infrastructure ò Environmental Impact ò Product Market Computer-based expertise has a potential to ò Capture perishable expertise, making this available for shared access and so reducing the cost of human experience ò Consolidate know-how for optimising process operations, bringing consistency of judgement and advice to decision- making by making the rules, facts and preferences explicit ò Allow assignment of the basis and authority of decisions, so experts can pass routine expertise down the line, freeing their time to generate more. ò Force a review of expertise when creating the knowledge base.

Jan 1, 1989

Flotation of Smithsonite by Using Siloxane Cationic Surfactants as Collectors

Sep 13, 2010

By D J. Brake

The correct specification and then selection of primary or major fans for an underground mine is a critical decision not only in terms of fan capital and operating costs, but also safety and reliability which usually has a major impact on mine production. In addition, fan manufacturers may spend tens of thousands of dollars preparing proposals for a purchase enquiry for primary fans especially where they have complete responsibility for the installation (turnkey projects). There are many good reasons to thoroughly and fairly adjudicate fan tenders. This paper describes the process to achieve this starting with the initial fan specification through to the final award.CITATION:Brake, D J, 2017. Fan specification and tender adjudication for mine ventilation engineers with particular reference to turnkey projects, in Proceedings Australian Mine Vent Conference 2017, pp 245–252 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By D Kay, M Lovitt

Mass Blasts are generally required at the completion of longhole stoping cycles to maximise the recovery of ore from a specific orebody. During the course of mining, the practice is to leave pillars of ore to support the opening left by extracted ore and to mitigate stresses from working areas of the stope. These pillars usually contain ore that has been included in the resource evaluation and is highly valuable to the mining operation. Due to their stressed nature, the removal of pillars by conventional blasting techniques, through small blasts, can result in pillars being reduced beyond their critical size and ultimately failing, rendering the ore unrecoverable. The AurionGold Kanowna Belle Gold Mine operates a Mine to Mill philosophy. This philosopy requires the fine tuning of blasting to provide the best possibe ore feed at the highest grade for mill productivity. This means that ore to the mill must be well fragmented from blasting that provides high extraction rates from draw points, with minimal dilution from overbreak or fall off, and sized to maximise SAG mill throughput. The AT04 Mass Blast contained significant ore reserves which were required to meet gold production targets. KBGB needed the AT04 Mass Blast to perform as well as if not better than conventional stope blasts to maintain mill production. This paper describes the circumstances, planning philosophy, techniques, including the use of Electronic Initiation Systems and Bulk Emulsion Explosives, and results that provided a highly successful outcome.

Jan 1, 2002

By M Svartsjaern, D Saiang and K Mäkitaavola

The Kiirunavaara mine is a large-scale (28 Mt/a) iron ore mine located in northern Sweden. The mine is owned and operated by Luossavaara-Kiirunavaara Aktiebolag (LKAB) using sublevel caving (SLC). The SLC area underlies an open pit decommissioned in the 1950s, the current main SLC haulage level is situated at an depth of 1100 m. The main orebody dips 60 degrees to the east with a distinct boundary defining the hanging wall to the east and footwall to the west. Since the 1980s damage has been observed both in the footwall rock mass as well as on the footwall crest of the open pit. Recent investigations indicate that the underground footwall damage is primarily controlled by large-scale slope failure mechanisms. Structurally controlled near-vertical planar shear failures in the upper footwall appear to be driven or facilitated by a step-path like curved shear failure situated in a zone starting ca 250 m, and intersecting the SLC about 100 m above the active mining level. To confirm this failure evolution a pilot underground measuring system has been designed and installed to monitor the expected rock mass displacements indicated by numerical models based on the above mechanisms. The systems consists of 50 m time domain reflectometry (TDR) coaxial cables installed in the footwall both across and away from an estimated damage extent boundary to monitor shear movements along natural joint surfaces. The TDR installation is combined with long extensometers to facilitate differentiation between diffuse shear and rock mass normal expansion. Additionally, a low-tech system of tape extensometer lines are installed in drifts and stopes running perpendicular to the ore strike to monitor horizontal displacements in the infrastructure as the footwall ‘slope’ loses confinement during mining advance when the mined out areas are replaced by caved rock from the hanging wall.CITATION:Svartsjaern, M, Saiang, D and Mäkitaavola, K, 2016. Underground footwall monitoring at the sublevel caving mine – Kiirunavaara, Sweden, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 773–780 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By J Weir

Accurate sampling of slurry streams is extremely important for metallurgical accounting in mining operations, not only for measuring the ore grade from the mine, but also for measuring the recovery of mineral by the mineral processing plant. Accurate sampling is also required for intermediate streams in complex circuits for determining efficiencies of processing units within the plant. As the profitability of the minerals industry is squeezed more with time, greater emphasis is being placed on efficient use of the resource and accountability of the various sections of the mining operations. This has led to increased awareness and interest in obtaining statistically correct sampling across the operations. Accurate sampling is not only required for metallurgical accounting, but is also required for on-line analysis of the slurry streams for elemental analysis and for particle size. Sampling of slurry streams for metallurgical accounting purposes has traditionally been one of the areas of concern in mineral processing plants. In the first instance, the sampler must be designed to comply with the fundamental principles of sampling theory and must provide a representative sample of the slurry stream. In the second instance, the sampler must continue to reliably provide a representative sample, regardless of wear of the equipment or build up of solids with time and other operating issues. To-date the main type of sampler that has been used in mineral processing plants for metallurgical accounting has been the Cross-Cut sampler. These have a cutter that periodically cuts across the full slurry stream. For large flow slurry streams, these are often followed by a secondary and perhaps a tertiary sampler, to reduce the flow-rate or sample, to a manageable size. This paper discusses a new method of sampling slurry streams that has been developed by Thermo Gamma-Metrics, previously known as Amdel Instrumentation. The new samplers overcome many of the problems associated with cross-cut samplers while providing a sample which is representative of the main stream, throughout the life of the sampling system. The sampler is called the SamStat (Sampling Station) and it is now proven in many applications across many countries and mineral processing plants (PGMs, Cu/Au, Pb/Zn, etc).

Jan 1, 2002

By C Dick

Over the past three decades, mining operations have seen a significant increase in the use of contractors for mining, camp management and catering, recruitment, maintenance, power management, and commissioning. More recently contractors have been engaged for stores and logistics, OH&S, environmental, exploration, training etc. In some countries, such as South Africa, the trend is towards total outsourcing of all aspects of a mining operation which is coordinated by the owners’ management team.During the Global Financial Crisis (GFC) more Australian companies considered and/or took on this approach to recruiting for both projects and operations as mining companies were forced to rethink their corporate strategies as commodity prices plummeted to low levels, pushing operations and projects into potentially financially unviable territory.This paper discusses the labour recruitment, commissioning and operating strategy of Western Areas NL (WSA), with the assistance of Independent Metallurgical Operations Pty Ltd (IMO), as it progressed construction, commissioning and operation of the Cosmic Boy nickel concentrator at the Forrestania Nickel Project during and post GFC. The use of IMO contractors allowed Western Areas to mitigate labour cost risk during the uncertainty caused by the GFC and let their management team focus on the task of bringing a new operation into viable and profitable production.

Aug 8, 2011

Enhancing the Flotability of Gold-Bearing Ores by a Mixture of Collectors

Sep 13, 2010

By S Paciornik

Computer-controlled microscopes with digital image acquisition and analysis led to the creation of the new field of digital microscopy. These techniques not only allow a certain degree of automation but have also brought new possibilities to microstructural characterisation. One of these new and promising possibilities is co-site microscopy, which links different kinds of information obtained from different microscopy techniques. The present work presents the development and implementation of a co-site microscopy methodology that combines images obtained by reflected light microscopy (RLM) and scanning electron microscopy (SEM). This methodology can improve the SEM analytical capacity by adding colour information from RLM. It involves the whole sequence, from image acquisition at the microscopes to the analysis of the phases using pattern recognition techniques. An automatic registration procedure for the two kinds of images was developed, allowing the adjustment of magnification, translation, rotation and pixel size, and the correction of local distortions. Thus, the images from RLM and SEM can be combined to build a multidimensional data set of each field, which can then be used in a pattern recognition approach to discriminate different phases. The methodology was tested with a copper ore sample, aiming at the discrimination of minerals that are not distinguishable with either RLM or SEM.

Jan 1, 2008

By A Manfrino

The Iron Bridge magnetite mine and infrastructure project is currently in development as a joint venture between Fortescue Metals Group, Formosa and Baosteel. It is supported by an extensive database of reverse circulation drill hole samples analysed by X-ray fluorescence (XRF), with a large subset tested for concentrate mass recovery, concentrate and tail grades by Davis tube recovery (DTR) testing. A limited number of rock physical testing results, including unconfined/uniaxial compressive strength and crushing work index, completes the database.By combining all available information – assays, DTR results, geology, stratigraphy, mineralogy and rock physical results – and using multivariate statistical analysis techniques, the impact of the critical factors that control concentrate quality, mass recovery and grindability characteristics have been outlined. A set of geochemical groups was created by using a cluster analysis technique from the combined XRF-DTR data. These groups allow optimal separation of material with consistently high concentrate Fe grades and mass recovery. This approach is superior to domaining based on stratigraphic logging or mass recovery as it is commonly used in standard magnetite estimation models. Using the results of a normative mineralogy study, the main geochemical groups were given a mineralogical profile fitting their geochemical characteristics. These findings further refined the understanding of the link between the process characteristics of the samples and their geochemical signature and mineralogy.The geochemical grouping defined on head grades and DTR concentrate mass recovery was generalised into a ‘geomet’ code based solely on the routinely assayed head grades, thus bypassing the need for systematic DTR testing. The geomet code identifies spatial domains with homogeneous geochemistry, mineralogy and process characteristics in both oxide and fresh material that form the basis of the current Iron Bridge resource model. The allocation of geometallurgical characteristics in terms of concentration amenability and concentrate characteristics on a block-by-block basis over the whole project allows for an optimum mine schedule and plant feed. This ensures that the desired concentrate characteristics and mass recovery can be better predicted over the life-of-mine, thereby improving the mine’s economics and stability by derisking the mine schedule and optimising the performance of the concentrators. A key benefit of the geomet code devised for the Iron Bridge mine is that it can be attributed in an automated manner to all samples analysed for a routine XRF analytical suite, from exploration to blasthole drilling. This allows each sample to be allocated to a geometallurgical material type with predictable process response in terms of concentrate mass recovery and concentrate quality without the need to complete systematic DTR testing.A standard multivariate analysis coupled with a cluster analysis has allowed the linking of interdisciplinary results between geology, mineralogy, geochemistry, process and metallurgy to better understand, predict and ultimately mine and process the Iron Bridge deposits. This allows plant operations and product quality to be optimised through each stage thanks to the predictable ore characteristics embedded in the mining model.CITATION:Manfrino, A, 2015. Unravelling the factors impacting on concentrate quality by geometallurgical data analysis at Fortescue Metals Group’s Iron Bridge magnetite mine, in Proceedings Iron Ore 2015, pp 567–578 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

Active geothermal fields show many of the characteristics seen in hydrothermal ore deposits but there are important differences as well. There are, for example, many differences in geology and chemistry between individual geothermal fields, even some nearby, and these include variations in host rock types (volcanic, sedimentary, plutonic and metamorphic), structures controlling fluid flow (normal, lateral, and, rarely, reverse faulting occur) and hydrological setting (valleys to elevated terrain).

Jan 1, 1986

By A Boucher, M Baudin, P Androszczuk, I Minniakhmetov, A Rigby, P Machado, M Wright, B Van Dijken

IGO Ltd’s (IGO’s) Nova Operation (Nova), which is 160 km east-north-east of the town of Norseman in Western Australia (WA), mines and processes nickel-copper-cobalt (Ni-Cu-Co) sulfide ore from the magmatic Nova-Bollinger Deposit (Nova-Bollinger), which is hosted by the Mesoproterozoic age high-grade metamorphic rocks of the Albany Fraser Orogen. Over its 56-month life-of-mine (LOM) operations to 31 December 2020, Nova has processed 5.63 Mt of ore grading 2.04 per cent Ni, 0.86 per cent Cu and 0.07 per cent Co from its underground mine. At the end of 2020, both the Nova-Bollinger JORC Code reportable Mineral Resource estimate (MRE) and Ore Reserve estimate (ORE) were >90 per cent classified in the highest JORC Code confidence categories of Measured Mineral Resource and Proved Ore Reserve respectively. The high JORC Code classification confidences assigned to the Nova-Bollinger MRE and ORE results from the 386 km of surface and underground diamond drill testing of the deposit to a nominal 12.5 by 12.5 m pierce point spacing in mineralisation. The close spaced high-quality drilling and bulk mining method employed at Nova has effectively removed the need for any grade control modelling outside of the MRE process. Importantly, having only the one fully drilled out deposit being mined and only the one process plant, Nova’s reconciliation process is in the fortunate situation of not being confounded by issues such as external ore sources and constant updates as new grade control information becomes available. IGO’s Nova reconciliation processes are focused on reconciliation ratios that quantify operational period differences between the MRE and ORE head grade and tonnage forecasts and the process plant head actuals. These metrics have been used to identify key reconciliation issues and have initiated several studies into the causes for specific reconciliation results, which are discussed in the paper. In late 2020, a period of sustained poor reconciliation results led to the recognition that increasing the understanding of risk between the MRE and ORE should be investigated. To assist with modelling stope level risk within the mine plan and subsequent reconciliation, an attempt was made to develop a formula to quantify ‘stope risk’ from MRE metrics such as sample spacing, kriging efficiency and so on

Mar 22, 2022

The ERMS Process was developed during four years of testwork by Austpac Gold NL to overcome the severe metallurgical problems of the ilmenite atWestport, in the South Island. These deposits have been known for about one hundred years. They were originally mined for gold, and only later attracted attention as a possible source of titanium minerals.   The resource is of world scale and may exceed 20 million tonnes of contained ilmenite. Similar deposits occur at Barrytown further south and together these areas would constitute an important opportunity for export-oriented mineral development, if a viable beneficiation technology were available. Further processing is essential, as the composition of the ilmenite is well below market specifications.

Jan 1, 1993