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By M Yahyaei, F Vos, J Siliezar

Site-based case studies (including data collected from industrial surveys) and their application in evaluating circuit performance, have a significant role in developing reliable process models. Such models are useful to both plant metallurgists and researchers. Appropriate process models enable the plant metallurgist to assess the impact of different operational parameters on the overall circuit performance. They also provide the researcher with a detailed understanding of process behaviour in response to changes in ore characteristics and process conditions (ie plant throughput, ore competence, ore type). Thus enabling the identification of effective operating factors, and allowing them to be ranked in order of their influence on the process response, which eventually develops into a process control tool in the hands of plant operators.The above approach has been developed and applied at the Julius Kruttschnitt Mineral Research Centre (JKMRC) separately for both comminution and flotation processes. In recent years, the JKMRC has attempted an integrated approach by developing process models that incorporate the impact of upstream processes on downstream processes. This is not possible using the traditional approach of separate comminution and flotation surveys, so conducting integrated plant surveys is crucial for success in developing integrated process models. This paper summarises industrial experience gained while conducting such an integrated plant survey at Glencore’s Ernest Henry Mining operation near Cloncurry in north Queensland. An appropriate approach should be taken to enable the alignment of different requirements from different processes during the plant survey. This, as well as the challenges faced in integrating comminution process models with flotation process models, are identified.CITATION:Yahyaei, M, Vos, F, Powell, M S, Siliezar, J and Perkins, T, 2014. Challenges in developing integrated process models based on industrial survey data, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 437–446 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By P Corbett, P Sheffield

Centennial Coal operates the Springvale longwall mining operation which extracts coal beneath the Newnes Plateau in the Western Coalfields of New South Wales. Springvale, and the neighbouring Angus Place mine, have a history of difficult geotechnical conditions where combinations of a relatively high stress regime and weak, laminated roof and extensive geological faulting has led to numerous roof failures throughout the mine’s life. Following development, the mines underground roadways can experience high levels of roof movement which may lead to roof falls. Multipoint wire extensometers are extensively used throughout the mine for roadway condition monitoring, and to reactively drive remedial strata support through trigger action response plans (TARPs).As a result of the use of high-density extensometer monitoring over a long period, the mines have an extensive archive of legacy data. Data processing has evolved over time in order to accommodate the increasing data volume, including direct data entry from the recently introduced hard-wired real-time monitoring instruments. It is likely that telemetric real-time instruments will be introduced in the future, which will cause another step change in data management requirements. This paper discusses the transition to and evolution of relational database management systems for extensometer and associated data.This paper also presents case studies of the use of a new software tool for reprocessing legacy data to enable time-scaled visualisation of monitoring data in the context of longwall and development face positions and installed strata support. The software can be used proactively in the identification of geotechnical risk factors and their interaction with the mining process to allow a more robust geotechnical hazard process. It interfaces directly with the widely used ExtoChart database software and can be presented with scale drawings of geological and geotechnical data to allow correlation of monitoring data results with risk factors.CITATION:Corbett, P and Sheffield, P, 2015. The use of high-intensity monitoring data to better characterise geotechnical properties of a non-homogeneous rock mass, in Proceedings Third International Future Mining Conference, pp 145–158 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By R J. Goldie

The Monty Copper Gold Deposit is an ultra-high grade mine in Sandfire Resource’s Doolgunna region which was completely drilled out and developed within two years of commencing mine development. During this period, a total of 986 grade control diamond drill holes were completed, assayed, and validated, 15 levels developed, and 3136 faces mapped. The aggressive schedule meant a high flow of geological data was produced, validated, and incorporated into regular geological model updates. To process this data at a rate which allowed for timely use, more robust data processing methodologies needed to be generated. A new validation system was implemented which required two levels of validation being applied to any diamond drilling update. Step one was the validation of initial physical data including survey pick-ups and logging. This was done prior to new drill data being added to the geological model. Step two was the validation of assay data which was required prior to resource estimation. The implementation of Seequent’s Leapfrog Geo modelling software also allowed for a more seamless and efficient modelling workflow. The use of the Leapfrog Geo vein systems allowed for more rapid generation of geological models which then afforded more time for stringent assessment of the mineralisation system. An example of this was the introduction of cross-shift peer reviews in which opposing rosters of geologists would rigorously evaluate the previous rosters work prior to reporting. This additional level of validation resulted in more robust geological models and the identification of new ore trends. This presentation will detail the evolution of the Monty Geological model from a simple tabular indicated resource into a complex highly refined measured resource. Themes will include how the model was produced using workflows developed and optimised to meet key deliverables.

Mar 22, 2022

A combination of the needs of business, employee desires and safety and health considerations is stimulating increasing attention to the time spent by people at work and the timing of that work. Particularly we are seeing: - innovative work schedules for 24-hour mining businesses; and - response from industry to accommodate the needs, even the desires, of employees in return for systems which are more productive and more capital efficient. There appears to be an evolutionary trend for business management to become more sophisticated and responsive to the need for achieving close to best cost work schedules to sustain continuous improvement. The underlying motivating forces driving this trend for improved techniques in organising attendance at, and time spent at work, is the seemingly inseparable combination of technological advance and ever-increasing accumulation of capital. The mining industry has not remained untouched by this thrust for ever-increasing need for best use of labour, to adopt advances in technology and to provide attractive opportunities for putting accumulated capital to work. An essential component of this on-going thrust is a substantial effort by the mining industry to improve the performance of labour by providing most-productive work schedules.

Jan 1, 1996

By A G. Grice

WMC Resources Pty Ltd û Copper Uranium Division operates the large underground Olympic Dam Mine at Roxby Downs, South Australia. These operations mine and process the ore to produce refined copper, uranium oxide, gold and silver. In mid-1996, the company committed to the Olympic Dam Expansion Project (OEP) to expand production from 3.0 million tonnes per annum of ore (85 000 tonnes per annum of copper metal) to over 9.0 million tonnes per annum of ore (over 200 000 tonnes per annum of copper metal). Along with the increase in the ore production capacity of the underground mine and the surface ore handling and processing facilities, expansion of the backfill system was required. The target backfill placement rate was 2.0 million cubic metres of backfill per annum which was to be predominantly delivered as cemented aggregate fill (CAF). This paper discusses the engineering activities undertaken to assess and change the method of designing the required strength of fill exposures. In addition, the operational changes that were introduced to achieve the required fill quantities and the mix designs to meet the specified strengths, including the use of alternate binders, are discussed. This work resulted in a large increase in the fill placement rate and a reduction in the overall unit cost of fill.

Jan 1, 2000

By Neill T. J, Howarth D. F, Malcolm J. McPhersqn

For many years Isa Mine has seen the need for a continuous mining machine which will economically cut hard rock. Tunnel borers are unsuitable due to the size and inflexibility of the machine and the shape of excavation mined. The design of roadheader type machines will not permit the use of the necessary cutting technology. in 1983 a joint project was undertaken by The Robbins Company and Mount Isa Mines Limited to develop and to trial a machine suitable for cutting hard rock in an operating mine. The project was based on the proven technology of raiseboring applied to horizontal development. The Mobile Miner was fabricated and trialled in a disused quarry in the U.S.A. during early 1984. Following these trials, the machine was transported to Mount Isa and commenced mining in September that year. The initial duty was to continue the development of a decline commenced by conventional mining for a conveyor system to serve the deeper southern areas of the 1100 copper orebody. This system will permit direct tipping of copper ore to a new crusher complex and conveying of the - crushed ore approximately 2 kilometres to the central hoisting shaft facilities. The Robbins Mobile Miner MM120-3001 uses a vertical rotating cutting wheel mounted on a horizontal swinging boom to excavate a nominally rectangular shaped heading. The cuttings are collected on an apron and conveyed back through the machine. The resulting excavation is smooth-walled with no blasting damage to the surrounding rock. This provides a safer working environment than does conventional drill and blast development mining. Ground support requirements are considerably reduced.

Jan 1, 1986

By A Halim

The European Union (EU) have recently issued new Threshold Limit Value-Time Weighted Average (TLV-TWA) for diesel exhaust contaminants, which are CO, NO2 and DPM. The new limits for CO and NO2 were issued in 2017 whilst the one for DPM was issued in 2019. However, in order to allow EU mines to formulate strategies to comply with these new limits, the EU granted a transition period in which mines could use the old limits until the new limits are enforced. The new limit for CO and NO2 will be enforced from 21 August 2023 whilst the one for DPM will be enforced from 21 February 2026. The new limit for NO2 and DPM is very low, 0.5 ppm for NO2 and 0.05 mg/m3 of Elemental Carbon (EC) for DPM. Combination of these two limits would be the lowest among all mining jurisdictions worldwide. It poses a huge compliance challenge to EU mines if they keep using diesel machines. Therefore, a study and a field trial were carried out by the author in 2019–2021 to investigate whether replacing diesel machines with Battery Electric Vehicles (BEVs) would be the best answer to this challenge. This paper outlines results of this study and field trial.

Oct 12, 2022

By R Castedo, P Segarra, L M. López, J A. Sanchidrián, A P. Santos

The cylinder test allows us to determine the expansion of a copper cylinder by the detonation of an explosive charge inside. This test, originally designed for military explosives, has been adapted for industrial explosives with non-ideal behaviour. From data obtained with this test and known physical relationships, an analytical procedure has been developed to calculate the Jones-Wilkins-Lee (JWL) equation of state parameters for five ammonium nitrate/fuel oil (ANFO) and six emulsion-type explosives. A new radial wall expansion function is proposed considering a non-zero initial velocity with the consequent positive Gurney energy at unit relative volume. A set of equations is established to determine the JWL parameters, three of them obtained at the Chapman-Jouguet (CJ) point and the other three at different relative volumes. These equations, along with some constraints to ensure a physically sound solution, are solved for the JWL parameters by a non-linear least squares scheme. A 2D Lagrangian axisymmetric finite elements (FE) numerical model is developed for each tested explosive to validate the analytical results, in terms of expansion histories, with good agreement. This confirms that the set of conditions, constraints on the parameters and least squares calculation used constitute a robust methodology that fully captures the physics of the detonation products expansion involved in the cylinder test.CITATION:Castedo, R, Sanchidrián, J A, López, L M, Segarra, P and Santos, A P, 2015. Jones-Wilkins-Lee parameters for civil explosives, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 57–64 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

The Honeymoon Well nickel sulphide deposits are located in the Agnew-Wiluna greenstone belt, about 45 km south of Wiluna. Both disseminated and massive sulphide nickel deposits are hosted by komatiitic rocks within the deformed and metamorphosed Honeymoon Well ultramafic complex. Fresh ultramafic bedrock is covered by up to 50 m of highly conductive transported material which greatly hampers both exploration and understanding of the bedrock geology. In the early-1970s, mineralisation was discovered by diamond drilling geochemical anomalies defined by wide-spaced percussion drilling over ultramafics that had been outlined by ground magnetics. Subsequent drilling has defined a resource of 158 Mt at 0.71 per cent nickel (based on 0.4 per cent nickel cut-off, 300 m below surface, December 1995) in four deposits. Over the life of the project a wide range of geophysical techniques have been used including airborne and ground magnetics, time domain clectromagnetics (EM), induced polarisation (IP)/resistivity, gravity and downhole techniques including EM, IP and physical property Measurements.

Jan 1, 1996

The first continuous pressure disk filter took up industrial-scale operation in Germany in 1976. This paper comments on major components of pressure filter facilities from the point of view of industrial-plant suppliers. For lack of time aspects of economy have not been commented upon. The paper elucidates a number of process-engineering inter-relations. It outlines important development trends from the angle of a machine-building company.

Jan 1, 1989

By Edwards A. B

Yampi Sound is a small channel in the Buccaneer Archapelago (latitude 16° 10' S.; longitude 123° 40' E.), on the northern coast of Western Australia (Fig. 1), about 90 miles north of Derby, and 200 miles north-east of Broome.The iron ore deposits of Yampi Sound occur on an approximately S.E.-N.W. trending belt of islands which form the northern boundary of the Sound (Fig. 2). From east to west they are Koolan Island, Tarrant Island, Usborne Island, Cockatoo Island, Irvine Island, Kathleen Island, Flora Island, and Bathurst Island. To the south of the Sound lie Margaret Island, which is separated from the mainland by a channel only 60 ft. wide, Dorothy Island, and Gibbings Island. Some of the channels between the...

Jan 1, 1938

By Y K. Leong

Iron ore tailings typically containing 40 to 50 per cent Fe can be beneficiated to iron ore products containing 54 to 60 per cent Fe. The impurities are comprised of clay, quartz, cristabolite and TiO2. Goethite and hematite are also present. At high concentrations of 55–60 wt% solids, the tailings displayed high yield stress and viscosity and cannot be pumped over long distances. Composite additives comprising of NaOH, phosphate-based additives and sodium metasilicate are found to reduce the viscosity and yield stress very significantly by a few orders of magnitude. The yield stress of 100 Pa can be reduced to almost zero. At this state, dilution of the tailings with its process water to 40 per cent solids causes the coarse and high-density iron ore particles to separate from the colloidal fractions located in the supernatant after a few minutes of sedimentation. Separation by decantation produces a sediment with an Fe content of 54 per cent from tailings with 47 per cent Fe. Another tailings sample with 48 per cent Fe was beneficiated to greater than 57 per cent Fe using NaOH-metasilicate-polyphosphate additives and employing an additional washing step. The use of other composite additives, NaOH and polyphosphates, increased beneficiated product Fe content to greater than 60 per cent from the same tailings. With the current iron ore spot price of more than US$180 per tonne, the cost of this treatment process even including a desalination step, if necessary, is relatively insignificant. This study has given tailings an economic value that should be exploited as soon as possible.

Nov 8, 2021

By K Knorr

Desktop X-ray powder diffraction using a D2 PHASER equipped with fast linear detector was performed on several iron ore and mill scale samples. Data were analysed using cluster analysis and Rietveld quantitative phase analysis. The quantitative mineralogy of both materials could be established. Thus the input is provided for understanding the energy consumption and the CO2 emission during iron production. Furthermore, tabletop XRD allows to distinguish iron ore from mill scales and to quantify their mixtures.

Jul 11, 2011

By N N. Viswanathan, D Kumar, S Kumar

In secondary steelmaking, calcium treatment is practised to modify the solid alumina or spinel inclusions into liquid or partially liquid calcium aluminates. It has been seen that the dissolved calcium reacts with sulfur or oxygen present in the steel to form CaS or CaO type of transient inclusions. Post-calcium treatment these transient inclusions further react with pre-existing alumina or spinel inclusions and modify them. In addition, direct modification of pre-existing inclusions is also reported in the literature. In the present study, laboratory-scale induction furnace-based experiments are carried out to melt electrolytic iron in an alumina crucible followed by deoxidation with aluminium. The CaS-based composite material, prepared in-house, is added after the aluminium deoxidation to study the stability of CaS at the steelmaking temperature. Multiple steel samples were also taken to track the dissociation of CaS by means of sulfur pick-up in steel. Additionally, inclusion analysis of these steel samples was also performed to track changes in the chemical composition of inclusions in response to CaS addition. It has been seen that the CaS dissociates leading to a gradual pick-up of sulfur in steel. The scanning electron microscope – energy dispersive X-ray spectroscopy (SEM-EDS) analysis reveals that the alumina crucible and floated alumina inclusions are modified into calcium aluminates and the extent of modification depends on the contact time of CaS with the two sources of alumina mentioned earlier. However, the modification of alumina inclusions in the bulk steel did not occur during these experiments.

Jun 19, 2024

The Gj0vik Olympic Mountain Hall is the world's largest underground cavern for public use and was created primarily to facilitate the ice hockey tournaments for the 1994 winter Olympics in Norway. The cavern has a span of 61 m, is 91 m long and is 25 m high. Ordinarily, rock caverns have a span width of 15 to 25 m, however, temporary mining caverns of up to 60 m have been excavated and natural caves with even greater dimensions occur. The Gj0vik Olympic Mountain Hall is unique as it is for public use with a capacity for 5800 spectators. Blasting was conducted with a high production rate at normal costs due to detailed planning and strict supervision of each round. The initiation system and vibration monitors were the main tools to control vibration levels and to facilitate a high production rate. It was of utmost importance that the rock remaining in the roofs and walls was of high quality after blasting to avoid rock fall, rock slides and excessive maintenance work.

Jan 1, 1995

By J R. Manuel, M J. Peterson

Selected drill core samples from a Ferrobamba-limestone-hosted, magnetite-haematite skarn deposit, located in the Apurimac department of the Andahuaylas-Yauri skarn/porphyry belt of south-eastern Peru, were mineralogically and texturally characterised to gain a preliminary indication of the deposit's potential as an iron ore resource. Optical microscopy, X-ray diffraction (XRD) and scanning electron microscopy/electron probe microanalysis (SEM/EPMA) techniques were utilised to determine the characteristics of magnetite, haematite and/or goethite dominated ore types, including variations in the relative proportions and textural relationships of the ore and gangue minerals. The deportment of elements deleterious to processing performance (eg copper, sulfur and potassium) was determined and the beneficiation potential of the samples was briefly assessed. In drill core sections, the ores are grey to reddish in colour, massive and 'metallic' to dark brown and earthy in character, moderately hard and porous (macro and microporous), with variable gangue infill. Ores often appear weathered, typified by ochreous goethite staining and common minor goethite (except in dense core fragments), occasionally exhibiting a more friable texture with coarse magnetite/martite grains. Silicates and lesser carbonate gangue are visible as blue-green to beige to white scaly and/or shaly surface coatings, and finely particulate infill, often goethite stained. Sulfide-rich ore types also occur in part of the deposit, but are restricted to specific drill holes. Magnetite grain size is relatively coarse, compared with magnetite from typical banded iron formations, whereas discrete silicate gangue is mainly bladed/fibrous and/or layered and micaceous in form. XRD analysis indicates the presence of vermiculite, serpentine, stilpnomelane, chlorite, actinolite and clays. There is a spectrum of ore types representing the gradation from 'fresh' (magnetite-dominated) to oxidised and weathered (martite/goethite-dominated). Martite-dominated samples are generally higher in grade, due to leaching and removal of silicate gangue, resulting in higher macroporosity. Where gangue has been leached out, partial replacement by vitreous goethite and/or hydrohaematite is typical, often preserving the fibrous/layered characteristics of the original silicates.

Jan 1, 2009

By G R. Dickens, N H. S Oliver

The genesis of giant hematite ore deposits in northwest Australia remains a contentious topic in part because key evidence supporting a unifying genetic model has not been found at all deposits. In particular, several papers have proposed that carbonate replacement of silica layers in banded iron formation (BIF) by basinal brines is a requisite first step toward ore formation. This initial hypogene stage is inferred primarily from the presence of silica-poor, carbonate-rich rocks found below ore and along normal faults at the Mount Tom Price and Giles Mini deposits. However, until recently such rocks have not been identified at the largest martite-microplaty hematite deposit, Mount Whaleback. In this study, samples of the upper Mount McRae Shale are examined for their chemistry, mineralogy and petrography. These samples were collected from several key locations, including within drill core that penetrates an area immediately beneath ore along the Mount Whaleback fault at Mount Whaleback. Compared to unaltered black shale from Wittenoom Gorge in the north and altered black and red shale at Mount Whaleback, reddish-green shale below the Mount Whaleback deposit is significantly enriched in MgO and CaO and depleted in SiO2. Samples of this shale consist predominantly of fine- to medium-grained dolomite and ankerite cut by chlorite and carbonate veins, contrasting with unaltered equivalents that contain mostly stilpnomelane, K-feldspar and relatively minor carbonates. This alteration is distinct from assemblages developed during regional metamorphism, and possibly represents hydrothermal alteration after metamorphism. Although several questions remain unanswered, these results support models that invoke an early hypogene stage during the formation of the martite-microplaty hematite deposits in the Hamersley Province.

Jan 1, 2005

By D J. Williams, M S. Zbik, A Shokouhi

There is a considerable difference in the particle size distribution (PSD) of clay mineral-rich coarse coal reject with variations in the test moisture state and the chemistry of the water used for testing. The coarse coal reject tested were collected from Jeebropilly Mine, located in the Ipswich Coalfields of south-eastern Queensland. Differences between the results of dry and wet sieving analysis indicate a significant breakdown of the clay mineral-rich coarse coal reject on wetting-up. Wet sieving caused a breakdown of the gravel-sized fraction to silt and clay size without significant breakdown to sand size. There is also a considerable variation in the results of hydrometer analyses of the clay mineral-rich coarse coal reject with variations in the chemistry of the water used, particularly at the fine end of the particle size range. The waters used included tap water, coal processing water and deionised water. In addition, the method of dispersion applied prior to hydrometer analysis can have a significant effect on the PSD of clay mineral-rich coarse coal reject, with boiling and sonic vibration causing the most breakdown of the clay particles. This paper describes the testing methodology used and the test results obtained, and attempts to explain the results in terms of clay mineralogy and water chemistry.CITATION:Shokouhi, A, Williams, D J and Zbik, M S, 2015. Influence of water on particle size distribution of clay mineral-rich coarse coal reject, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 239–246 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By Lloyd F, Arnold D. A, Hagan T. O

This paper investigates the problems that are encountered in mining at extreme depths. It looks into the rock mechanic aspects, especially the high stress levels that will occur, and the hazard of rockbursts. Furthermore, environmental problems are discussed, with refrigeration and reduction of neat loads being major methods of maintaining ,sorkable conditions. The paper concludes that it will be of tmost importance to have a planning team of Tne highest quality to ensure that conditions are maintained so that work can be carried out safely and under reasonable conditions.

Jan 1, 1986

By D Morrison, P Goodman

The cycle time between adjacent stopes is critical to achieving the required production rate from 3500 Orebody; one of the Enterprise Mine orebodies. Current Mt Isa cemented fills require a 90-day cure period which had to be cut to 30 days while maintaining the required strength criteria. The Enterprise Mine Feasibility Study recommended that this be achieved by Cemented Slurry Rock Fill (CSRF), but that on-going research into paste fill be continued. The continuation of the research, in conjunction with overseas visits has recommended that the 3500 Orebody be filled with paste fill, with the potential to fill other orebodies. The paste fill will comprise cyclone and thickener dewatered copper tailings to which Portland Cement (PC) is added before vertical borehole delivery and undergound pipeline reticulation to individual stopes. The benefit is not only re-use of copper tailings but also much reduced binder usage.

Jan 1, 1998