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By K Niiranen

Luossavaara-Kiirunavaara AB (LKAB) operates one iron ore mine, three concentration plants and three pelletising plants in Kiruna, Sweden. The current methods of separation at the beneficiation plants are low intensity magnetic separation (LIMS) and reverse apatite flotation, where the wet LIMS stage is regarded as the crucial part of silica separation from the ore. Because future silica levels are expected to increase in the incoming material to the beneficiation plants, geometallurgy has become an important area of development and research.A laboratory-scale methodology was developed for the systematic characterisation of the ore for mineral processing, with the focus on the high silica ore type B2 and newly discovered subtypes. This methodology combines mineralogical, geochemical and process mineralogical characteristics. Automated mineralogy (QEMSCAN®) is used to study the modal mineralogy, the distribution of silicate minerals in different particle size classes after comminution, the deportment of silicon (Si) between various silicates and the degree of liberation and intergrowth of magnetite and silicates. An essential stage in the systematic characterisation of the ore deposit for mineral processing is the estimation and simulation of different parameters from the laboratory scale to the full scale at the concentration plants. This is achieved by using empirical models based on the data collected at the mineral processing plants. As the first step to implement the geometallurgical information, the current geological model is reconstructed with the mineralogy and the two, newly defined subtypes of high silica ore type B2 are separated into different domains.To study the reduction of the SiO2 content in the magnetite concentrate, a large-scale reverse cationic silicate flotation laboratory test program was initiated in early spring 2016. This program investigated potential silicate flotation in the beneficiation plants at the Kiirunavaara site. The second target is to implant mineral processing parameters into the block model based on the new geological model. This information provides a good basis for making a prognosis for mine planning and a quality prognosis regarding the crude ore for mineral processing.CITATION:Niiranen, K, 2017. A geometallurgical perspective on a high-grade iron ore deposit at Kiirunavaara, northern Sweden, in Proceedings Iron Ore 2017, pp 309–318 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By D O’Dea, B Godel, T Honeyands, B Ellis, T Harvey

X-ray computed tomography (XCT) is a non-destructive technique that allows the exploration of the internal structure of solid objects in 3D. Over the past ten years, the combination of XCT with more conventional 2D techniques and quantitative 3D image processing and analysis (commonly referred to as digital rocks) has allowed us to address some of the most challenging problems in ore deposit studies. The range of X-ray energies used in XCT allows the X-rays to be transmitted through complex and dense materials including iron ores (eg sinters, lumps, granules). Recent high-resolution XCT scanners have the ability to generate multiscale (25 down to 0.3 µm voxel size) imaging of a given sample enabling the characterisation of 3D textures across a range of scales. This paper will focus on the application of digital rocks to iron ore sinter particles (using filtered polychromatic X-ray beam). The paper is divided into three parts and includes: i) details on the methodologies including their benefits and limitations and the effect of spatial resolution; (ii) the quantification of pore network topology and pore characteristics (eg open versus closed pores, pore size distribution and pore morphologies; degree of connectivity of the pore network and its tortuosity); and (iii) the evaluation of the technique to characterise various phases within the material and quantify 3D mineral textures.CITATION:Godel, B, Ellis, B, O’Dea, D, Honeyands, T and Harvey, T, 2017. Digital rocks for iron ore sinters – towards a D quantification of sinter textures, in Proceedings Iron Ore 2017, pp 529–534 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By X Hu, C-C Yang, J Pan

In this work, preheating and roasting tests of pellets made from blends of Western Australia ultra-fine (WAU) magnetite concentrate and Chinese domestic magnetite concentrate or Brazilian hematite concentrate were carried out. The results showed that pellets made from 100 per cent WAU magnetite concentrate possesses inferior preheating and roasting performance when preheating at 1050°C for 20 minutes and roasting at 1300°C for 40 minutes, the compressive strength of preheated and fired pellets is 502 N/pellet and 2313 N/pellet, respectively. When 40 per cent Chinese domestic magnetite concentrate or 20 per cent Brazilian hematite concentrate was blended with 60 per cent or 80 per cent WAU magnetite concentrate, the appropriate preheating temperature of the pellets are reduced from 1050°C to 950°C and 975°C, and also the firing temperature of two types pellets are decreased from 1300°C to 1250°C and 1280°C respectively. Moreover, the compressive strength of fired pellets is obviously improved up to 2746 N/pellet and 2630 N/pellet respectively. Microstructure analysis of the fired pellets made from 100 per cent WAU shows its poor growth of Fe2O3 grains, low interlinkage degree of hematite grains, small size of crystallised grains and high porosity of pellet; however, the fired pellets that blended with domestic magnetite concentrate or with Brazilian hematite concentrate have fully growth of Fe2O3 grains, closer interlinkage of hematite grains, lower porosity and stronger consolidation. The preheating and roasting performance of WAU magnetite concentrate pellets can be improved by optimising ore matching.CITATION:Pan, J, Hu, X, Zhu, D-Q and Yang, C-C, 2017. Pelletising performance of Western Australian ultra-fine magnetite concentrate and strengthening technique by optimising ore matching, in Proceedings Iron Ore 2017, pp 97–104 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By C Li, D O’Dea, R Moreno-Atanasio, T Honeyands

The behaviour of iron ore granules in the feeding process of sintering is significantly influenced by the material properties of the granulated mix. Therefore, the measurement of key material properties of the iron ore granulated mix is indispensable prior to the simulation of the sintering process based on the discrete element method (DEM). In this paper, three key property parameters of the iron ore granulated mix, apparent density, elastic modulus and rolling friction coefficient, were measured in laboratory-scale experiments. For different sintering processes, the moisture content of the granulated mix normally varies according to the specific requirements for granule size distribution and operating conditions. Therefore, understanding the effect of moisture content on the property parameters of iron ore granules is very helpful in accurately determining the property parameters for DEM simulation work. In this paper, six groups of iron ore granule samples with six levels of moisture contents were prepared through granulation and the trends in apparent density, elastic modulus and rolling friction coefficient with the increase of moisture content were plotted and analysed based on the measurement results. The results show that as moisture increases from 6.9 per cent to 9.1 per cent, the apparent density decreases from about 3000 to 2800 kg/m3. With moisture increasing within the same range, the elastic modulus first decreases from over 200 MPa to below 100 MPa and then reaches a relative constant value of about 40 MPa at higher moisture contents. Rolling friction coefficients are measured using two methods with both indicating a similar trend, with the rolling friction coefficient first decreasing and then rising as moisture increases from 6.9 per cent to 9.1 per cent. The relationship between µr and µ’r is assumed to be similar to that between static and dynamic friction coefficients.CITATION:Li, C, Moreno-Atanasio, R, O’Dea, D and Honeyands, T, 2017. Variation in property parameters of iron ore granulated mix with moisture content, in Proceedings Iron Ore 2017, pp 79–84 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By C Simpson

The Pilbara region of Western Australia is well known for its abundant exports of hematite-goethite deposits, which have been mined and exported since the 1960s. Magnetite has also been mined in Australia throughout this period, although historically of much lower production volumes (WA Iron Ore profile, 2016). Magnetite offers a source supply of material >66 per cent iron grade product, which is used as premium feed (predominantly pellets) to blast furnaces or specialised steel mills.The Iron Bridge project area contains outcropping magnetite and hematite banded iron formation (BIF), which within the region was recognised as having potential to host economic mineralisation during the 1960s. Development within the project area, however, did not commence until Fortescue Metals Group acquired the tenements based on a 2004 agreement, formed a joint venture with interested groups and then initiated an assessment for magnetite (rather than hematite) mining potential. The combined deposits now have an identified large mineral resource inventory, with test work demonstrating they are able to produce a magnetite concentrate of greater than 66 per cent Fe over an extended mine life. This concentrate would be suitable for forming pellets or feed for direct reduced iron products.The deposits form a singular orebody, approximately 12 km in length by 1 km in width and extending to depths beyond 600 m. The four main deposits are geographically separate and have subtle mineralogical differences, thought driven by the degree of deformation and alteration within each area.Definition of the stratigraphy, structure and key mineralogy of the deposits has been carried out through several stages of exploration and project development. This has also included recent mining and processing of more than 1 Mt of feed material to an on-site processing facility. This demonstrated at a production scale that dry plus wet processing techniques can efficiently separate the magnetite from the gangue minerals to form a suitable (marketable) product.Geometallurgical classification of the host stratigraphy has been carried out from analysing the high volume of quantitative data available for this deposit. This has allowed definition of mappable units within the fresh BIF to be used as a driver in mine scheduling, delivering optimal feed to the processing plant.Construction of mine and processing facilities is expected to commence once all technical risks have been addressed, market conditions are deemed appropriate and approval is given by the joint venture partners.CITATION:Simpson, C, 2017. The Iron Bridge magnetite deposits, in Proceedings Iron Ore 2017, pp 287–294 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By T J. Beardsmore, N Wyche, D Flint, T J. Griffin

Western Australia (WA) is currently the world’s largest iron ore producer, and mining of its huge reserves and resources of iron ore has become a critical part of the state’s economy and regional development. Iron ore exports from WA have reached 760 Mt/a, corresponding to shipping more than one Mt per turn-of-the-tide from the state’s ports. The iron ore sector dominates all commodities produced in WA, and in 2016 accounted for 77 per cent of the state’s royalty receipts, 56 per cent of mineral and petroleum exports (by value) and 50 per cent of mining industry employment. Expenditure on exploration for iron ore (including that for resource estimation and conversion to ore reserves) has declined markedly, from its record peak of $1100 M in 2012 to $280 M in 2016, placing it second after gold. Foreign investment has been a key element underpinning development of the iron ore industry from the 1960s until today, and will likely continue to be so into the future.CITATION:Flint, D, Wyche, N, Beardsmore, T J and Griffin, T J, 2017. The importance of iron ore to Western Australia’s economy, in Proceedings Iron Ore 2017, pp 7–12 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By X Dahe

SLon vertical ring and pulsating high gradient magnetic separators (VPHGMS) possess the advantages of high efficiency and high reliability in beneficiating weakly magnetic minerals. In recent years, models SLon-2250, SLon-2500, SLon-3000 and SLon-4000 have been developed. This paper gives several examples of their applications in oxidised iron ore and ilmenite processing flow sheets to improve iron and ilmenite recoveries.CITATION:Dahe, X, 2017. Recent development and application of SLon vertical ring and pulsating high gradient magnetic separators in the iron ore and ilmenite processing industries, in Proceedings Iron Ore 2017, pp 461–466 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By D M. Hunter, S M. Iveson, K P. Galvin

For low density materials such as coal, density-based fractionation of particles via the sink-float method is relatively simple due to the availability of liquids of suitable density; however, for high density minerals, suitable heavy liquids are less available and those that are available are expensive and pose significant hazards. At best, sink-float separation can be performed up to densities of 4400 kg/m3 with the use of Clerici’s solution at elevated temperatures. Hence the direct measurement of grade-recovery and density-partition curves is problematic. Therefore, in most cases, beneficiation plants must rely on methods such as QEMSCAN, density tracer particles or very limited information to guide them in the design and optimisation of their plants.This paper describes a density-fractionation method utilising laminar flow through a system of parallel inclined channels to generate a series of overflow fractions at different flow velocities. Here the particles are subject to precise hydrodynamic forces with minimal dispersion or mixing. The size distribution of each overflow fraction at a given flow velocity is obtained using a laser particle size analyser, and combined with a laminar flow model to deduce the corresponding density distribution. The paper describes the application of the method to measure the separation achieved using a REFLUX Classifier to obtain the corresponding feed, product and reject ‘washability curves’, and in turn the full partition surface. Approaches used to corroborate the findings are discussed.CITATION:Hunter, D M, Iveson, S M and Galvin, K P, 2017. A batch elutriation technique for the density-based fractionation of iron ore, in Proceedings Iron Ore 2017, pp 195–104 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By M I. Pownceby, S Hapugoda, V Nunna

Deposits of low-grade iron ores containing abundant goethite are distributed across the world. A common difficulty associated with beneficiating goethitic-rich ores is the poor liberation characteristics of the iron-bearing minerals which often contain finely disseminated gangue minerals such as kaolinite, gibbsite and quartz. Microwave-assisted heating has been proposed as an effective way of inducing dehydroxylation and associated mineral transformations in order to beneficiate low-grade goethitic ores. In this research, the mineral transformations occurring in a low-grade goethite-rich sample using microwave radiation was studied. Roasting conditions (up to 1000°C and under various CO/CO2 gas atmospheres) were designed to generate a magnetic product from a goethite-rich, reject waste stream sample sourced from an iron ore processing site in the Pilbara, Western Australia. Conditions (T, pO2) for transforming the raw material from hydrated goethite to hematite and eventually to magnetite are presented. Chemical and mineralogical characterisation of the raw material and roast products were conducted using X-ray fluorescence, X-ray diffraction, optical microscopy and scanning electron microscopy techniques to identify the mineralogical and chemical changes occurring during the heat treatment. Further steps are suggested to optimise the microwave-assisted magnetising roasting and correlate it with the application of magnetic separation techniques to maximise the efficiency of upgrading the iron content in low-grade iron ores.CITATION:Nunna, V, Hapugoda, S and Pownceby, M I, 2017. Study of microwave-assisted magnetising roasting and mineral transformation of low-grade goethite iron ores, in Proceedings Iron Ore 2017, pp 575–582 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By L O. Filippov, C H. Veloso de Melo, A Correa De Araujo

Froth flotation of iron ores is one of the most widely used methods to upgrade iron ore into high-grade concentrates. In recent years, reverse cationic flotation of iron ores has been specifically the subject of several studies. Since quartz is the most common gangue mineral in iron ores, understanding the behaviour of this mineral was the main target of the majority of such studies. However, with the depletion of mineral deposits considered rich and easy to process, it has become more common to find iron ores with complex gangue minerals, which are composed not only of quartz but by a variety of silicates. The mineralogical composition of the ore is an important factor for determining reagents and mineral processing parameters. The mineralogical suite of an ore also presents a paramount role for operational optimisation of any given flotation process. Some studies were performed with different types of amphiboles and other Fe-bearing silicates, for example, but the influence of the mineralogical nature of these silicates in reverse cationic flotation has not been fully explored and will be discussed here. Changes in the traditionally used reagent scheme for reverse cationic flotation, generally including alkaline pH values, polysaccharides as depressant (mainly starches) and primary ether amines and diamines, are expected when dealing with iron ores with complex silicate gangue composition.CITATION:Veloso de Melo, C H, Correa de Araujo, A and Filippov, L O, 2017. Reverse cationic flotation of iron ores with complex silicate gangue minerals, in Proceedings Iron Ore 2017, pp 241–244 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By R Wilson, R Williams, B Freeburn

McLanahan RSS14x50 scrubber screens have individually processed over 50 Mt of Pilbara iron ore. The first stage of separation in these plants with abrasive, high specific gravity, large lumps is an extremely arduous duty with high wear rates. With the Scrubber Screen layout this occurs in the attached trommel section. The initial supply of the replaceable trommel panels were of steel-backed rubber with a service life of approx. six weeks. Site Personnel established a goal of 26 week wear life in conjunction with 100 per cent reliability and while field trials were undertaken using a variety of hardened and cast steels that demonstrated wear life to the nominated requirement some unpredicted failures still occurred. With a long evaluation time and challenges to create repeatable conditions with field testing, a purpose built test unit was designed and constructed to allow controlled evaluation of a number of materials and designs. During 2016 tests were conducted with eight different materials, of varying thickness to simulate impact conditions and a number of aperture profiles to evaluate both impact and abrasion effects. From these results two designs were selected for full scale implementation to confirm the nominated goals. This paper will present details of both testing procedures and results of all materials, as well as conclusions of successful field implementation.CITATION:Wilson, R, Freeburn, B and Williams, R, 2017. Trommel panel development for iron ore applications, in Proceedings Iron Ore 2017, pp 251–256 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By R A. M Maddever, P Jeanneau, V Flahaut

Over the entire life cycle of a mine, from early resource evaluation to the blasting of benches, the collection of geochemical data is crucial for the site operator, who must routinely and intensively drill and sample the orebody. This produces huge numbers of physical samples, in turn requiring significant cost and time for their preparation and assay. Moreover, despite best efforts, the sample recovery process is prone to error, which limits the quality of data.The pulsed neutron gamma technique has been used for decades in various industries, in particular oil logging, for its ability to provide direct identification and quantification of elemental concentrations. However, its implementation in logging tools for the mining sector is relatively recent. Built around the latest in technology for optimal spectrometric measurement, a commercial tool referred to as FastGrade™ 100 has been available for a few years and used with increasing success in the mining environment, specifically the iron ore industry, resulting in a reduction in the amount of collected samples. Relying on the physics of neutrons and gamma photons, both of which are particles that penetrate the surrounding bedrock through several tens of centimetres, such spectroscopy tools measure in real-time the composition of a much larger volume than the delimited volume of the drilled material traditionally used for geochemical mapping. Better statistics and reliability of the estimated composition increase the ability to properly and quickly measure drilled holes and allow the substituting of all or part of the sampling and assaying efforts by geochemical log data. Our paper focuses on this technology, known as pulsed fast and thermal neutron analysis (PFTNA). It reviews the main drivers for the design of such a logging tool and discusses how the fundamental characteristics of the technology, in terms of neutrons and gamma interactions, translate into interpretation of the analytical output.CITATION:Jeanneau, P, Flahaut, V and Maddever, R A M, 2017. Iron ore benefits from neutron pulsed geochemical tools, in Proceedings Iron Ore 2017, pp 387–396 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By E Portes, G Noble, J Roberto, A Stabile

Iron ore beneficiation plants are facing economic pressures to treat more challenging ore types, improve efficiency and improve product quality. Better control and stability of the plant process in the face of increasing feed ore variability has been a goal for many of the operations facing these challenges.Prompt gamma neutron activation analysis (PGNAA) technology has proven to be a successful measurement technique within an iron ore beneficiation plant. PGNAA was first developed in the early 1980s for the measurement of the elemental composition of bulk materials. Today, PGNAA technology is applied for elemental analysis within the iron ore industry on both bulk materials and slurries.Traditional composite sampling throughout the wet iron ore beneficiation process provides a delayed measurement of average properties but does not capture the true variability of the process in real-time. As such this is a limiting factor towards stabilisation and optimisation of the process. A PGNAA analyser provides real-time slurry elemental analysis of feed, concentrate and tails streams within the processing plant. The analytical data from the analyser can be exploited with a control strategy to correct and stabilise the plant on a much shorter time scale, delivering significant economic benefits and greater operational flexibility. The economic benefits include more stable product quality and a reduction in composite sampling and laboratory costs.Some example results will be presented from the Vale Vargem Grande iron ore beneficiation plants, which are utilising a six stream multiplexed Thermo Scientific PGNAA Slurry Analyser.CITATION:Noble, G, Stabile, A, Portes, E and Roberto, J, 2017. Real-time slurry elemental analyser for iron ore beneficiation plant control, in Proceedings Iron Ore 2017, pp 481–486 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By Y X. Xue, J Pan, D Q. Zhu

In order to reveal the correlation between the fundamental sintering characteristics of iron ores and their real sintering behaviours, a comprehensive evaluation index is proposed based on the measurement of four high temperature indexes, ie assimilation temperature, liquid phase bonding strength, liquid fluidity and calcium ferrite formation percentage, and the sintering pot tests of single ore fines and their blends. The results show that both the lowest assimilation temperature and liquid fluidity of ore blends appear to be the linear superposition of those of single iron ores except for the liquid phase bonding strength and calcium ferrite formation percentage. Furthermore, the tumble index of the sinter product obtained from blended iron ores also corresponds to a linear superposition of that of single ores, but not for the solid fuel rate and productivity. The comprehensive strength index YT exhibits a credible linear positive correlation with the four high temperature reactivity indexes, whereas the comprehensive productivity index YP possesses a lower correlation with the four high temperature reactivity indexes. The comprehensive strength index YT developed can predict the tumble index of the sinter product quite well, but the comprehensive productivity index YP cannot be used to evaluate the productivity effectively.CITATION:Zhu, D Q, Xue, Y X, Pan, J and Shi, B J, 2017. Correlation between high temperature sintering characteristics and sintering behaviours of iron ore fines, in Proceedings Iron Ore 2017, pp 123–132 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By D O’Dea, B Godel, T Honeyands, G Evans, T Harvey

The pores within iron ore sinter are important for producing a high quality material that is strong and easily reduced. The complementary methods of mercury intrusion porosimetry (MIP) and X-ray computed tomography (CT) were used to characterise the structure of industrial and pilot scales sinters across a wide range of pore sizes (3 nm to 100 µm for MIP and 50 µm to 5 mm for CT). The inhomogeneous nature of sinter and the variation in the measurements make it difficult to compare samples. The generalised additive modelling (GAM) approach, using the open source statistical software package, R, has been applied to highlight where there are peaks in the concentration of pore sizes. Importantly, the shape of the GAM-fitted function and the heights of the peaks show statistically significant differences between samples. For the samples investigated, the GAM-fitted functions for the MIP volume distribution of pore diameters were found to have a common set of distinctive peaks at 0.005, 0.6 and 20 µm. The GAM approach was also applied to the X-ray CT measured pore wall thickness, highlighting a single peak whose position varies between samples. The cause of these distinctive peaks and their implications for sinter quality are discussed. Correlation was found between the volume in peak 1 (0.005 µm) and the concentration of primary hematite. No correlation was found between the pore wall thickness and the strength of the sinter, suggesting the composition of the pore walls may be more important. Future work will focus on small-scale sinters produced under tightly controlled conditions to study sinters with a wider range of quality values.CITATION:Harvey, T, O’Dea, D, Evans, G, Godel, B and Honeyands, T, 2017. Highlighting key features of the pore structure of iron ore sinter using mercury intrusion porosimetry and X-ray computed tomography, in Proceedings Iron Ore 2017, pp 39–48 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By D FitzGerald, S Jakica, R Paterson, J Silic

A new 2.5D airborne electromagnetic (AEM) algorithm has been developed by Intrepid Geophysics and Jovan Silic & Associates. The advantage of 2.5D (2D geology, 3D source) AEM inversion in 3D geological mapping applications and identification of conductive drilling targets, compared to the more commonly used conductivity-depth imaging (CDI) transforms or 1D inversions, are demonstrated using examples from banded iron formations (BIFs) and other geological settings. We show emerging AEM systems are capable of providing estimates of economic rock unit thicknesses, dips and fault definition at an accuracy that mitigates the need for pattern drilling.The 2.5D inversion application used in this work and described in Silic et al (2015) is a substantially changed version of ArjunAir (Wilson, Raiche and Sugeng, 2006), a product of CSIRO/AMIRA project P223F. The changes include a new forward model algorithm and a new inversion solver. The application enables the accurate simulation of 3D source excitation for full domain models inclusive of topography, non-conforming boundaries and very high resistivity contrasts. Solution is accurate for a geoelectrical cross-section, which is relatively constant along a strike length that exceeds the AEM system footprint.The major innovation includes a new inversion solver with adaptive regularisation, which allows the incorporation of a misfit to the reference model and the model smoothness function.Memory usage has been dramatically reduced and is estimated prior to execution. For speed the software has been parallelised using Intel message passing interface (MPI) and can be used on standard computing hardware or computing clusters. Data from survey lines with lengths exceeding 100 km can be inverted on high end laptop computers.We allow flexibility in the selection of components and in the estimation of noise.AEM inversion examples are shown for surveys from BIFs, base metals (volcanogenic massive sulfides) and geological mapping projects and the results are compared with known geology and drilling. We demonstrate the much improved mapping and target definition delivered by this inversion method when compared with the other more common transforms or inversion methods used on these projects.CITATION:Paterson, R, Silic, J, FitzGerald, D and Jakica, S, 2017. High accuracy .D airborne electromagnetic inversion method for banded iron formation and other geological settings, in Proceedings Iron Ore 2017, pp 319–330 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By P W. Wypych

The iron ore industry faces significant challenges in the control of dust to meet emissions regulations and goals, as well as ensuring sustainable operations. This paper describes some of the different techniques and innovative technologies that are being developed and implemented to improve the suppression of airborne dust, specifically through the use of high energy micromist sprays. The utilisation of computational fluid dynamics (CFD) modelling and simulation is identified and described as a key enabling technology for an improvement in dust suppression solutions both from a level of understanding the source and flow of dust emissions, and for the development of new systems that can be used in the iron ore industry. CFD modelling is shown to be effective for modelling both spray dispersion and cross-wind effects, allowing designers to develop high-efficiency dust suppression systems with a greatly improved level of confidence when compared to traditional techniques. New high energy micromist technology is also outlined as a key element in developing high-efficiency dust suppression systems. Experimental results and industry applications are presented to demonstrate the significant improvements that can be achieved in suppressing or reducing airborne dust emissions.CITATION:Roberts, J M and Wypych, P W, 2017. Research into improving the efficiency of water spraying airborne dust control techniques in the iron ore industry, in Proceedings Iron Ore 2017, pp 359–364 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By A T. Job, M L. Edgar, P R. McAree

Characterising ores in-pit and in real-time presents a significant value opportunity for the mining industry. Hyperspectral imaging systems are proposed as an enabling technology to achieve this real-time characterisation. This paper considers the application of a hyperspectral imaging spectrometer mounted on a shovel. We define the performance requirements for such a spectrometer and associated subsystems during a typical dig-load cycle. The relatively high swing rotation speed of the shovel requires approximately video-rate exposure times to achieve good spatial resolution. We analyse a selection of components against these requirements and find that suitable commercial spectrometers, detectors and optics appear fit-for-purpose. Automated, real-time spectral classification systems are also available, with only relatively modest requirements for processing power. The paper argues that at near peak solar illumination, a system for field deployment at the required sensitivity is viable using only commercial off-the-shelf components.CITATION:Job, A T, Edgar, M L and McAree, P R, 2017. Real-time shovel-mounted coal or ore sensing, in Proceedings Iron Ore 2017, pp 397–406 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By J Guo, K Williams, J Y. Guo, A W. Roberts, M Jones, B Chen

Numerical simulations using the discrete element method (DEM) were carried out to investigate the flow patterns and stress field redistribution at the hopper and feeder interface. The influences of different filling heights, belt speeds and clearances between the hopper bottom and feeder surface on feeder loads were studied. Meanwhile, experiments were conducted by utilising wedged plane-flow hoppers with different configurations and horizontal feeders with various clearances. The simulation results were compared with theoretical values and experimental measurements. In terms of the cases presented in this study, simulation results reveal good agreements with experimental observations regarding the flow pattern. Being similar to the theoretical values, the simulations provide close predictions on vertical feeder loads for steady flow states, but they may show significant overestimations for initial states. Additionally, suggestions are given for relevant simulation parameters based on the comparisons shown in this investigation.CITATION:Guo, J, Roberts, A W, Williams, K, Jones, M, Chen, B and Guo, Y J, 2017. Simulation investigation of flow patterns and feeder loads at hopper/feeder interface, in Proceedings Iron Ore 2017, pp 173–182 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By M I. Pownceby, N A. S Webster, R Pattel, N Ware

The decrease in quality of Australian iron ore, coupled with the demand for more efficient energy use, necessitates closer monitoring and optimisation of process conditions for iron ore sinter production. Sinter properties are correlated with the mineralogical content and traditionally, quality control has relied on methods such as Fe2+ determination, point counting via optical microscopy and automated electron beam techniques such as QEMSCAN; these can have a typical turnaround time of several days between sampling and reporting of results. As well, there is additional uncertainty around quantifying some of the complex mineralogical phases in sinter such as silico-ferrite of calcium and aluminium (SFCA) and SFCA-I, which are key phases influencing sinter quality. There is a clear need for the implementation of alternative analytical methodologies that offer a turnaround in hours or even minutes to provide information to accurately maintain production conditions.X-ray diffraction (XRD) is a technique widely used for the quantitative mineralogical phase analysis (QPA) of ores and processed materials in the iron ore industry. Partial least squares regression (PLSR) analysis methods have recently been suggested as an indicator of sinter Fe2+ content from powder XRD data without the need for rigorous and often time-consuming mineralogical analysis by the operator. In this study we provide results from the implementation of PLSR to predict the strength of iron ore sinter. Results are sourced from a well-constrained data set comprising strength properties (as quantified by a tumble index (TI)) from a series of compact laboratory test samples. Using this data set it was determined that PLSR has potential to be used as a method for calculation of sinter TI from powder XRD data and, therefore, process control.CITATION:Webster, N A S, Pownceby, M I, Ware, N and Pattel, R, 2017. Predicting iron ore sinter strength through X-ray diffraction analysis, in Proceedings Iron Ore 2017, pp 331–334 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017