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By Pratt V

The economic, social and political environment of the mining and minerals industries is, as we all know, volatile and affected by constantly changing international forces. In addition, the outcome of negotiations with overseas customers is often uncertain for long periods, or even unfavourable. The industries and companies represented at this Conference are in an arena of high competition, risk taking and enormous capital outlay. They are industries which our overseas markets (rightly or wrongly) have criticised for industrial relations problems, unreliable production and uncertain deliveries. They are industries which have an urgent need to be cost effective and competitive at all levels of activity.A critical factor in the mining and metallurgy industries is, therefore, its human resources and its human resource management. It requires the full use of available talent, innovation, skills and qualifications within its workforce, and the appropriate management of these resources.

Jan 1, 1985

The Australian coal industry has undergone sevenfold growth over the last 30 years and since 1985 has been the world's largest coal exporter. Three quarters of Australia's coal production is exported so its future is dependent on it remaining internationally competitive with other energy sources and other coal exporting countries. Coal is likely to increase its share of the energy market during the nine- ties as oil prices increase, new coal-fired capacity is commissioned and some form of nuclear energy is developed which is of acceptable safety standards to the community for use in the 21st century. Gas may take a part of coal's anticipated market share by the Year 2000. While coal exports will increase from China, Colombia, Indonesia and Venezuela and satisfy some of this additional coal demand Australia will also expand its export production, due to its existing advantages. The United States, Canada, South Africa, Poland and USSR seem unlikely to enjoy the same degrees of expansion and some, particularly Poland and USSR, will decline. Australia will always find it difficult to compete in the more distant markets due to levels of ocean freight, although its high quality coals will tend to partly offset such disadvantage.

Jan 1, 1988

Xstrata CopperÆs Mount Isa Copper Operations is located in mineral rich north-west Queensland and is one of the largest sources of copper in the world. This world-class underground operation is planned to produce over 6.6 million tonnes of copper ore in 2007 from the X41 and Enterprise Mines. With an underground mining history of over 50 years and underground reserves of over 83 million tonnes at 2.6 per cent copper, mine planning for the future becomes an exciting challenge for the technical team due to the older nature of certain areas. The 1100 Orebody of the X41 mine was one of the first places that copper mining occurred, with its discovery in 1953 - 1954 and mining commencing in the 1960s. Sublevel open stoping mining methods have been employed since that time as the means of extraction, using a primary-secondary sequence to maximise stope turnaround time. Large Transverse Pillars within the 1100 orebody were not mined out in order to provide access for ventilation, power, orepasses and other services. The Panel Pillar, 4180XC and 4010XC pillars are three such Transverse Pillars in the 1100 orebody that will be mined as a final retreat. This paper discusses the technical challenges and issues associated with the extraction of Q390 stope, one of the stopes located in the Panel Pillar, and the design solutions to overcome these issues. Managing the exposure of backfilled stopes of variable fill strength, ensuring the stability of the crown, stope walls and drawpoints, managing vertical openings, re-establishing service networks, and stope filling are the critical issues given consideration for the final design of Q390 stope and other such stopes within a Transverse Pillar. Communication and coordination between the different departments in the mine are essential for the necessary work to be completed in a timely manner to bring pillar stopes into production.

Jan 1, 2007

Using Dynamic Simulation Throughout a Process Plant's Life Cycle

Sep 13, 2010

At the Waikato North Head Ironsand operation, NZ Steel Mining Ltd is using a Bucket Wheel Excavator û shiftable conveyor mining system to excavate Titanomagnetite bearing sand and clay. The system utilises two Bucket Wheel Excavators with a two level shiftable bench conveyor and common trunk conveyor to deliver the material to a processing plant. The system was commissioned in November 1984 and has proved itself to be a high capacity, low cost method of excavating. Techniques of handling high sand faces have been developed and the conveyor layouts are going through a process of change to cope with the variable geo technical conditions and remain within: the characteristics of the excavators. The safety requirements for operating the system have been of a high standard and the experience has increased the confidence of the Company and the Mines Department Inspector's, for the first Bucket Wheel Excavator Mining system in New Zealand.

Jan 1, 1986

By A Batnasan

The main techniques for removing phosphorus as an impurity element in iron ores are physical separation (eg magnetic separation, flotation) and chemical separation (acid leaching, alkaline leaching and bioleaching) processes. When phosphorus occurs in iron ores as phosphate minerals (eg apatite), physical separation techniques are available to remove the gangue minerals from iron ores. On the other hand, chemical separation techniques are suitable for reducing phosphorus levels when phosphorus is associated with iron oxides and hydroxide minerals (eg hematite and goethite) in iron ores. In this study, the dephosphorisation behaviour of high‐phosphorus iron ore was investigated using a combined alkaline roasting and water washing route. Roasting experiments were conducted in a laboratory electric muffle furnace using various concentrations of sodium hydroxide (0–50 g/kg-ore) at different temperatures (100–800°C), varying prolonged roasting times (0–2 h), and different particle size fractions (-45 – -250 μm) of iron ore. Subsequent water washing experiments were employed at various pulp densities (30–1000 g/L) and different times (30 s – 60 min) at ambient temperature. Hematite and goethite were the main minerals in the high-phosphorus iron ore identified using X-ray diffraction (XRD) analysis. The iron ore assaying 63.40 mass % Fe (total), 0.240 mass % P, 4.53 mass % SiO2, and 4.87 mass % Al2O3 were determined using X-ray fluorescence (XRF) analysis. The results showed that the dephosphorisation rate of the iron ore was reached 40 per cent under roasting with 50 g/kg-ore NaOH at 300°C for 2 hours followed by water washing for 30 s with a pulp density of 300 g/L, reducing phosphorus level from 0.240 mass % to 0.142 mass %. At the same time, the iron grade was reduced from 63.4 per cent to 59.5 per cent, caused by an iron loss. Results suggest that the phase transformation of goethite induces the dephosphorisation of high-phosphorus iron ore under alkaline roasting conditions

Aug 22, 2022

By Z Zhao

Coal dust is hazardous to underground coal workers and water spray is the most common and economic method for controlling coal dust. Previous studies proved that the addition of surfactants can improve the performance of water spray on coal dust suppression. The evaluation methods for surfactants vary from different studies. The zeta potential test is a common method for evaluating surfactants with ionicity. Generally, the suspension of coal dust with pure water usually showed a negative value of zeta potential. The addition of cationic surfactants can increase the zeta potential to a positive value with a small dosage, while the addition of anionic surfactants can only lower the zeta potential. However, there is a lack of comprehensive study to investigate the relationship between the zeta potential and the suppression performance for coal dust. The aim of this study is to reveal the consistency and discrepancy between the zeta potential and the suppression efficiency of a surfactant. Firstly, the mixture of cationic surfactant solutions and coal dust would be evaluated by the zeta potential test. The wind tunnel tests would then be conducted for the same surfactant solutions to measure and calculate the suppression efficiency. It was found that the addition of surfactant can increase the zeta potential and the suppression efficiency and it reached the greatest efficiency when the zeta potential approached to zero. The equilibrium of zeta potential can benefit the suppression performance of surfactants in the wind tunnel test. The result of this study can achieve a better understanding of the mechanism for coal dust suppression. The selection of surfactants will also be suggested for researchers or industries in terms of coal dust control. It would be more economic if a similar performance could be achieved by less consumption of surfactants.

Oct 12, 2022

By G M. Zhomin, A S. Arkhipin, A Kondratiev

Viscosity of multicomponent slags is one of the crucial physicochemical properties for many industrial processes and technologies. While the viscosity-temperature relationship of completely molten slags can well be described by an Arrhenian-type law, the compositional dependence of viscosity is still not fully understood, especially in compositional regions with the lack of experimental data (eg at the glass-former concentration of 90 molar per cent or higher). In the present work major compositional relationships of the activation energy of viscous flow have been revised for numerous binary and ternary slag systems on the basis of experimental data collected and stored in the viscosity database OxiVis. For example, it has been found that the activation energy relevant to the polymerisation effect in binary systems of the MO-GFO type, where MO is the modifier oxide (ie monovalent K2O, Na2O, Li2O and bivalent CaO, MgO, BaO, MnO, PbO etc) and GFO is the glass-forming oxide (SiO2 or B2O3) is not always proportional to the third power of XGFO (contrary to the Urbain formalism) and can vary significantly dependent on the slag system. Also, the activation energy of the charge compensation effect has been revised for ternary systems of the AO-MO-GFO and AO-MO type, where AO is the amphoteric oxide (Al2O3, Fe2O3 or other). A simple polynomial model has been proposed on the basis of the carried-out analysis for estimation of viscosities of multicomponent slag systems. The model has been optimised against the experimental viscosities in the selected binary, ternary, and higher-order oxide systems and has been shown reasonable agreement with the experimental data.

Aug 21, 2024

By A J. Morrison, K Demir, J Kohmuench, K Runge, C Evans

The Eriez HydroFloat® is a flotation device capable of recovering significantly coarser and lessliberated particles than is possible using a conventional mechanical flotation cell. Originally developed for industrial and bulk mineral beneficiation, the HydroFloat® is attracting increasing interest as a means of increasing the required grind size for metalliferous ore flotation. Doing so would reduce the costs of processing complex ores, either by decreasing the energy required to grind the flotation feed or by increasing the throughput achievable with a given comminution circuit. Processing coarser particles would also result in coarser waste streams, potentially improving the mechanical and hydraulic performance of the waste dams that they are sent to. Recent work at pilot – and industrial-scale has proven the potential of the HydroFloat® technology to achieve these gains in metalliferous applications. However, in order to realise the full potential of the HydroFloat® technology, it is necessary to understand not just its performance but also the drivers for that performance. Doing so will allow the design and operation of HydroFloat® devices to be optimised for different ores and applications. For this work, a HydroFloat® pilot rig was deployed to a coppergold plant in Australia and was used to investigate the effect of stream and operating conditions for treating the tailings stream of one of the plant’s rougher flotation cells. Under each set of operating conditions, samples were taken of the HydroFloat® feed, tailings and concentrate streams, and processed to yield the grade and recovery achieved by the device. At the same time, the bubble size and bed behaviour inside the device were measured. This paper presents preliminary relationships observed between the operating conditions and the performance of the HydroFloat® cell, and thus suggests a range of possible drivers for the measured coarse particle flotation performance.

Aug 24, 2022

By S Natsui, Y Goto, S Kawanishi, J Takahashi, H Nogami

The demand for copper increases yearly, and further improvements in copper smelting efficiency using flash furnaces are required. This study was conducted to understand and promote the interfacial reaction associated with the collision of silica flux and iron oxide particles, ie the formation reaction of fayalite slag, in the reaction shaft of the flash furnace. High-temperature microscopy was used to observe the reaction behaviour of a 2 mm granular SiO2 reagent in contact with micrometreorder- sized FeO reagents in situ. When the amount of FeO was lower than the stoichiometric amount with SiO2, the molten slag formed at the interface between FeO and SiO2 diffused into the SiO2 particle before dissolving the remaining FeO particles. It did not contribute to the subsequent reaction, and despite having the lowest amount of FeO among the samples in this study, many unreacted FeO particles remained on the surface of the samples after testing. On the other hand, under conditions with high FeO content and close to the eutectic composition of the FeO-SiO2 system, a liquid phase formed from low temperatures, gradually increasing in volume and eventually completely dissolving the 2 mm SiO2 grain. These results indicate that the early-stage slag is essential in increasing the interfacial area between FeO and SiO2 and facilitating the supply of FeO to SiO2. In other words, the FeO/SiO2 determines the amount of liquid phase and significantly influences the subsequent interfacial reaction rate between FeO and SiO2. Therefore, the local FeO/SiO2 of the particles falling down the reaction shaft should also be optimised to ensure early slag formation. Meanwhile, the time required for 2 mm SiO2 to complete the reaction for the temperature history employed in this study was significantly longer than the particle residence time in the reaction shaft. Further detailed investigation of the effects of silica flux particle size, composition, and reaction temperature on the reaction time will help find the conditions under which the reaction of silica flux can be completed in the reaction shaft. These kinetic approaches could contribute to future innovations in the copper smelting process using flash furnaces.

Jun 19, 2024

By Q Qu

Reliable prediction of longwall gas emission sources and rate plays a critical role in mine ventilation and methane drainage capacity planning. Over the years, Australian longwall mines have been using the historic Winter method and the Flugge method in modelling specific gas emissions (SGE). The predicted results often experience high discrepancies from the operational reality. To improve gas emission prediction, post-mining gas contents were measured in several mines in Qld and NSW by safely drilling core holes into the longwall goaf. The results revealed many new insights into gas emission characteristics from different coal seams and the drawbacks of the European methods in their use in high-production gassy Australian longwall mines. Based on measurement data, a new, time-dependent gas emission prediction model has been developed. Considering several factors such as caving, desorption and production rate, the new model can predict more accurate and meaningful gas emissions to meet today’s needs in mine gas emission management. A case study is provided to demonstrate the application of the new SGE model.

Oct 12, 2022

By C McGuire

As mobile equipment electrification in underground mining continues to gain popularity, control ofheat and humidity in the workplace is becoming a key driver in sizing of ventilation and mine aircooling systems. For design and sizing of ventilation and cooling systems to be accurate, and for themine mobile equipment fleet to be sized appropriately to meet production goals, vehicle productivitymetrics, heat modelling, and energy balances for electrified fleets need to consider operation througha realistic duty cycle that is reflective of various tasks performed during a shift.The authors conducted a real-world comparison of two 8 cubic yard (14 metric tonne) class Load-Haul-Dump (LHD) machines – one diesel and one battery-electric vehicle (BEV) – performingidentical muck-haul-dump operations on consecutive days at an underground nickel/copper hardrock mine in Ontario, Canada.The battery-electric LHD averaged 8.9 per cent faster cycle time than the diesel vehicle (gross,without accounting for charging time), and was able to transport 25 per cent more material per cycledue to a larger bucket capacity. When including the charging time, average net cycle times wereequivalent for the two vehicles over the 200 cycles. The BEV carried more payload over the eighthour period due to the increased capacity per cycle.The testing identified an approximately five-fold reduction in heat output from the BEV in comparisonto the diesel LHD on a basis of heat output per tonne of rated bucket capacity. Heat output from thefast charger was found to be approximately 4 per cent of the charging rate, with negligibletemperature change observed in the main drift. External noise levels in the mine were found to be14 dB lower for the BEV during transit and 11 dB lower during bucket loading. Fuel/energy costs forBEV electricity input were approximately four times lower per operating hour than diesel fuel costbased on typical 2021 electrical and diesel unit rates for a grid-connected mine in Ontario, Canada.

Oct 12, 2022

By Y Lanwin

The Australian mining industry, a cornerstone of the nation’s economy, is on a journey towards greater equity and inclusion. Th paper introduces a comprehensive exploration of how universal design principles, stemming from architectural roots, have evolved through automation and digital technology into the more encompassing frameworks of inclusive design and equitable design. The paper proposes a practical framework for those involved in work, facilities and equipment design in the mining industry to identify and assess for equity and inclusion. Universal Design emerged in the 1960s with a primary focus on architecture, aiming to create spaces accessible to people of all abilities. Its foundational principles sought to ensure equitable use, flexibility, simplicity, perceptibility, tolerance for error, low physical effort and optimal spatial considerations. Over time, these principles evolved and expanded beyond physical spaces, finding applications in various fields, including technology, education and transportation. In response to advancements in technology and a growing understanding of the multifaceted nature of diversity, Universal Design evolved into Inclusive Design. Inclusive Design goes further than mere accessibility, considering a broader spectrum of users with varying cognitive, sensory, cultural and socio-economic backgrounds. It emphasises user centred design, customisation options, diverse user research and continuous iteration. Equitable Design emerged as a framework that addresses not only the diversity of needs but also systemic disparities. It emphasises fairness, justice and the elimination of structural inequities. Equitable Design encompasses accessibility and affordability, representation and diversity, ethical considerations and community engagement. This paper will explore the applications of these design principles through a series of case studies including village and on-site facilities, remote operations and office based work design and technology design. By applying these frameworks in a mining context, the paper proposes that mining companies and suppliers can improve diversity, equity and inclusion leading to safer, more engaged and productive workplaces.

Apr 16, 2024

By D Corley, J Moore, M Grant, A, W R

Resource estimates are the corner stone of technical and investment decision-making. Prior to mining, resource estimation uncertainty has the greatest potential to lead to poor investment decisions, despite a significant component of resource estimation uncertainty being unknowable at this critical stage in the mining cycle. This presents a conundrum to the resource geologist in terms of risk evaluation and resource classification. Ahead of mining, there is normally considerable focus on drill hole spacing analysis to determine the ‘optimal’ drill hole spacing, taking grade and geological continuity into account; cost-benefit analyses balance improved resource definition against cost; the law of diminishing returns and the exponential cost increases acting together as spacing is reduced. Typically, a lower limit to the drill hole spacing is identified. After completing the resource drilling to an agreed spacing, resource estimation is then undertaken. At this point it is common to attempt to bracket the resource estimation uncertainty. In many cases conditional simulation is used, based on a modelled, but largely assumed, variogram model. It is also assumed that the histogram of the available drill hole sample data is representative of the in-ground mineralisation. The purpose of this paper is not to diminish the importance of drill hole spacing and simulation studies, but rather to illuminate an important aspect of estimation uncertainty that, although previously recognised, is typically overlooked – the question of how representative the available data set is in characterising the true (but unknown) distribution of mineralisation. To do this, we lift the lid on one of OceanaGold’s former operations, the mined-out Globe Progress Mine, by resurrecting a high quality, close-spaced, reverse circulation (RC) grade control data set. The Globe Progress Mine is within the West Coast Region of New Zealand, it was closed and transitioned to rehabilitation in 2016 and is now known as the Reefton Restoration Project. The exhaustive Globe Progress grade control data was used to repeatedly ‘redrill’ the deposit by extracting 35 m × 35 m spaced subsets from the original 5 m × 5 m spaced grade control data. Utilising closely spaced grade control data removed the need for assumptions regarding short range continuity, which are necessary with forward-looking analyses that are based upon broader spaced resource drilling. The extraction process used a nearest neighbourhood algorithm, repeatedly moving the origin in 5 mE, or 5 mN increments. Individual resource estimates were then completed for each of the extracted drill hole data sets (49 in total) as well as a grade control estimate based upon the exhaustive data set. Whilst the data unpinning each of the 49 estimates changed, the geological assumptions, variography, and modelling parameters remained constant. This approach was taken to isolate the impact of changing the input data. The 49 estimates were then compared against each other and the grade control estimate. The mean of all 49 sensitivity estimates was close to that of the grade control estimate in terms of contained gold, tonnes and grade. Whilst it is acknowledged that the grade control estimate itself is subject to some degree of estimation uncertainty, the close match between the average of the 49 estimates and the grade control estimate suggests that the resource estimation methodology is reasonable and appropriate. Whilst this comparison is important, the focus of this study is on the component of estimation uncertainty related to the underlying data, and this is reflected in the spread across the estimates. The spread across the 49 global estimates (highest to lowest) for this particular Mineral Resource Estimation Conference 2023 | Perth, Australia | 24–25 May 2023 142 case study was found to be significant (approximately 20 per cent in grade and metal) and that is attributable solely to the underlying data. This exercise quantifies a component of the estimation uncertainty that is inherent to all drill hole data and is distinct from the uncertainties associated with modelling methodology choices, sample and subsample quality and drill hole spacing-related interpolation uncertainty. Importantly, this uncertainty is unknowable prior to mining; we can only directly compare the resource drill hole data against grade control data after mining has taken place. For the case study, approximately 65 per cent of the estimates fell within 5 per cent of the grade control estimate for contained-gold, suggesting that for many projects the histogram of drill hole data is unlikely to differ noticeably from that of the in-ground resource. However, about 15 per cent of the estimates in this study differed by more than 7.5 per cent, suggesting that a not-insignificant proportion of estimates will be materially compromised. Whether or not the available drill hole data is representative comes down to the ‘luck of the draw’ and cannot be known at the time of resource estimation. Given the challenge of attempting to evaluate forward-looking estimation uncertainty, a component of which that can only be quantified retrospectively, what should we do as resource geologists? What are the implications for risk evaluation, resource classification and reconciliation? Furthermore, without rigorous post-mining data checks, resource geologists may conflate suboptimal modelling with the shortcomings of the underlying data. An example of this problem is discussed in the following section.

May 24, 2023

By T Hicks

Designers of mining facilities play a significant role in defining the overall mine greenhouse gas emissions performance. This demands an appreciation of all the greenhouse gas emissions sources, including Scope 3 emissions, which will form an increasing fraction of the emissions as we transition our generation sources to renewable energy. Traditionally overland conveyors are designed to operate as fast as practical, and through this approach, achieve relative minimisation of: conveyor belt tensions; belt width; mechanical equipment masses; structural steel quantities; and concrete quantities. It is well understood that higher belt speeds reduce capital cost and improve project economics. Operating at higher speeds introduces operating costs through system energy losses and increased wear rates. This paper assesses the life cycle greenhouse gas emissions for a typical iron ore overland conveyor to demonstrate how the design criteria and engineering decisions impact greenhouse gas emissions and project economics. An analysis of the decarbonisation potential and project economics using a range of operational parameters has been completed, developing a marginal abatement cost for each system configuration, creating a basis for integration of low emission overland conveyor designs as part of the broader facility decarbonisation strategy.

Sep 1, 2024

By S Hapugoda, J R. Manuel, X Cao, B D. McDonald, N A. Ware, L Lu

Roy Hill is a large iron ore mining, processing, railing and port operation in the Pilbara region of Western Australia. Since delivering its first shipments to customers in December 2015, Roy Hill has quickly achieved a 60 Mtpa production rate of lump and fines products. The process plant, principally consisting of wet scrubbing, screening and de-sanding unit processes, was expanded from early 2020 to include operation of a Wet High Intensity Magnetic Separation (WHIMS) Plant. The WHIMS Plant treats tailings to recover approximately 4 Mtpa of ultra-fine (nominally -150 μm) high-grade hematitic concentrate which, after dewatering, is blended into the fines product. Unlike typical hematite concentrates, which consist largely of dense particles with smooth surfaces, the WHIMS concentrate is characterised by very finely microporous hematitic/goethitic particles, reflecting the overall characteristics of the Roy Hill deposit. Detailed test work has been conducted in collaboration with CSIRO to characterise the WHIMS concentrate in terms of its physical and mineralogical properties, and to determine its influence on the granulation and sintering performance of Roy Hill fines – from fundamental/lab-scale and sinterpot perspectives. The results demonstrate that blending of the high-grade hematitic Roy Hill WHIMS concentrate into the fines product can maintain overall sinter quality and positively influence granulation and sinter melt formation, as well as Fe grade.

Nov 8, 2021

By Y Lin, B J. Seligmann, M Hassall, S Micklethwaite

For multi-site mining companies, checking the quality and consistency of the data recorded in risk registers is important for confirming how well mine safety management systems have been implemented. However, this task is complicated by the differences in scope of the site, their particular nature, the complexity of the operations and many other factors that can introduce nuances to the characteristics of the risk registers. We present here an application of a technique called Causal Network Topology Analysis for comparing the quality and consistency of risk registers. By quality we refer to, for example: - missing causal relationships between risks - location of missing controls - focus of risk treatment strategies: prevention versus mitigation controls. By consistency we refer to how causally interdependent are the risk events. There are often causal interactions between the lines of a risk register that mean that the likelihood and consequence scores that are applied to each risk event are not independent. We measure this degree of interactions by: - proportion of independent scenarios per register - efficiency of risk treatment strategy comparison. This approach can indicate quality and consistency differences between registers irrespective of the actual details of the site or operation. This occurs by comparing aspects of the structure of a causal network extracted from how the risk events, causes, controls and consequences causally interact. In this work we compare pairs of registers to demonstrate the approach.

Apr 16, 2024

By H Kurth, L Balzan

The potential for bulk diversion was identified and quickly implemented following the development of bulk sensing technologies applied to conveyed flows. In the early 1980s real time analysis of ash in coal was intended to improve the understanding and control of quality variability. By the end of the 1980s approximately 5% of coal analysers installed were being utilised for bulk sorting; diverting flows to create stockpiles to improve blending flexibility and boiler feed consistency, diverting waste material, or bypassing the beneficiation process when the coal met product quality criteria. In the 1990s bulk sensing and sorting utilising natural gamma detection was applied to conveyed waste in gold-uranium mineralisation and allowed ore to be recovered and processed that would otherwise have been discarded. Further applications developed in the iron ore sector where product quality ore could be diverted to bypass beneficiation and save significant unnecessary processing costs and improve recovery by avoiding process inefficiency losses. Plant capacity was freed up to be utilised by material that required processing. Similar benefits became evident in the phosphate industry and in base metals where multi-elemental analysis using Prompt Gamma Neutron Activation Analysis provides ideal opportunities to representatively measure 30 second conveyed increments at high accuracies. This has been successfully adopted in copper, nickel, platinum and lead-zinc to improve waste removal after primary crushing to eliminate unnecessary expense and improve plant efficiency. The benefits include increased output from existing operating capacity, significant reductions in consumable costs and generation of fewer detrimental waste streams. The paper outlines the technologies and discusses case studies covering the above commodities, demonstrating the immense value that representative real time measurement of conveyed flows can create. Measurement data concurrently provides multiple benefits in operational performance besides sorting, through ore reconciliation, ore blending, feedforward control and metal accounting, adding further value.

Nov 10, 2020

By D Gagnon, P Bouchard, F Vanier, E Soares de Lima Filho, J El-Haddad, M Sabsabi, G J. Wilkie, A Beauchesne, A Hamel, A Blouin, T Vaillancourt, F Boismenu, A Harhira, A Plugatyr, C Padioleau

Quantitative mineralogy is an established discipline in the geosciences and is aimed at providing mineral grade and texture information for geological and mineral processing applications. The two core technologies underpinning Quantitative Mineralogical Analysis (QMA) are Scanning Electron Microscopy (SEM) in combination with Energy-dispersive X-ray Spectroscopy (EDS). Technologies such as QEMSCAN and MLA are now routinely used to optimise the performance of large-scale mineral processing plants in the base and precious metal sectors. One of the major disadvantages of the QMA methods used today is extensive sample preparation requirements which make application of this technique to real-time mineralogical characterization not feasible. A breakthrough has been achieved by the National Research Council Canada in collaboration with CRC ORE by developing a novel Laser Induced Breakdown Spectroscopy (LIBS) based technology capable of real-time mineralogical characterization of process streams without sample preparation. The potential applications of this technology include, but not limited to, in-pit muck piles, underground draw points, cross-belt analysis as well as slurries. This paper describes the development of the LIBS-based technology from a proof-of-concept (TRL2) to the construction of a prototype sensor and its validation in a simulated environment (TRL5). Future work is being planned to test and further validate the LIBS sensor on a mine-site which will progress the technology to its next readiness level (TRL6).

Nov 10, 2020

By M Lak, R Amiri, A Haratian, M Asghari, S Haji

In recent years, due to advances in designing of various magnet assemblies, a wide range of magnetic materials with different properties can be concentrated. Jalal Abad iron ore beneficiation plant, which is located in Iran, Kerman province, is currently producing iron ore concentrate with the capacity of 0.8 Mt/a by having medium intensity magnetic separators (MIMS) with rougher and cleaner stages that finally leads to the production of an iron concentrate with the Fe grade of about 65 per cent. In this plant, the rougher tailings directly goes to the thickener as the final tailings and cleaner tailings feeds to the ball mill for regrinding. Since some hematite particles with weak magnetic properties cannot be recovered from only these two stages of magnetic separation, the obtained tailings from this concentration plant has approximately an iron grade of 25 per cent to 27 per cent. Accordingly, laboratory processing tests were conducted on the obtained representative sample of the final tailings. Based on the experimental results performed on final tailings, a new magnetic drum separator with a specific magnetic assembly was designed that could finally lead to product with iron grade range of 58 per cent to 60 per cent with relative and total weight per cent of 8.6 per cent and 3.86 per cent. Finally, it could be concluded that feeding of magnetite particles to the existing drum separators, due to their high magnetic field intensity, cannot efficiently lead to improvement of the grade of concentrate. Therefore, pilot magnetic separation tests were done on the final concentrate for evaluation of product upgrading probability. Consequently, by increasing another stage of cleaning and by decreasing the magnetic field intensity, the final product grade could be enhanced from 65 per cent to 67 per cent.

Nov 8, 2021