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By M S. Tuohy

Since the independent review of fatal accidents in the mining industry carried out by Dr Sean Brady (the ‘Brady Review’), High Reliability Organisations (HROs) and their operating principles have been discussed across the Queensland mining sector. HROs are organisations said to consistently avoid serious failures, reliably delivering their organisational objectives despite operating in environments characterised by high levels of inherent risk and/or operational complexity. HRO concepts have previously found application in other similarly hazardous industries to mining. However, as Hopkins (2009) pointed out, HROs ‘are very elusive creatures that inhabit the realm of theory more than the real world’. The Queensland Resources Council (QRC) with support from the Commissioner for Resources Safety and Health initiated a review of how HRO principles can be translated to the mining industry. The review was conducted by Noetic, an Australian management consulting company that specialises in hazardous industries, including mining and metals, and has prior experience applying HRO theory.

May 5, 2022

By A Castillo, K Wiese, L Panduro Robles

For decades, organisations worldwide have been working to overcome challenges associated with new technology adoption while keeping up with rapid growth, development, and globalisation. In minerals processing, the challenges in developing and implementing solutions that contribute to the mining value chain are unique from other markets, as mining operations expect that world-class suppliers provide them solutions to gain a competitive advantage in their operation, production, performance as a financial asset, and as a long-term partner as we move into the future of mining. A simple shift in mindset is proven key to successful technology implementation. Change leaders must no longer think of their expertise in the area of application as their only responsibility; they must make a mental shift and see themselves in dual roles that strive to integrate the perspectives and needs of both developers and users. Successful change leaders must: (1) collaborate, seeking user involvement to ensure fit between product and operational needs, (2) demonstrate commitment to receive new technology, and (3) communicate to achieve an eventual shift of ownership from supplier to users that is seamless. Additionally, this strategy contributes to the mining value chain, as it allows developers and implementers to evaluate how change contributes to the asset’s position both within the company and in the commodities market. This paper will explain the shift in perspective for new technology implementation in detail and provide recommendations that operations can emulate, using examples of real challenges and lessons learned during a commissioning of the CYCLONEtrac™ Particle Size Tracking (PST) system at Cerro Verde’s C2 Concentrator. This concentrator has led technological change for plant optimisation, witnessed improved Net Metal Production (NMP), among other benefits with PST, the only technology in the market capable of providing real-time, online, and direct particle size measurement at the individual hydrocyclone level

Aug 24, 2022

By C Linklater, J Chapman, A Watson

Closure options under consideration at some sites include backfilling mined-out pits with waste rock. Backfill may include mineralised and non-mineralised waste rock. Following groundwater rebound, flow-through conditions may develop in the pit post-closure. The backfill located in the saturated zone below the water table may release solutes under such conditions. It is therefore important to understand the potential impacts that backfilled pits could have on postclosure groundwater quality.Geochemical characterisation programs are the foundation for assessing the potential chemistry of water that has contacted mined wastes. Such programs must be designed to obtain data relevant to the closure options under consideration. To complement standard testing techniques, SRK utilises saturated column testing designed to generate data on leaching rates under anoxic conditions that could be encountered within submerged backfill.This paper presents the findings of saturated column test work carried out on waste rock samples from an iron ore mine in the Pilbara.CITATION:Watson, A, Linklater, C and Chapman, J, 2016. Backfilled pits – laboratory-scale tests for assessing impacts on groundwater quality, in Proceedings Life-of-Mine 2016 Conference , pp 110–114 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By R Carstens, L Munsamy, L Prinsloo, C Huang, C Zhang, R Liang, I Canbulat

With recent advances in machine learning, data-based automated decision-making has been proven successful with promising outcomes in many industries. Its application in the mining sector can be ground-breaking; particularly the data-driven analytics that can support decision-making in the mine and consequently enhance mine safety, efficiency and sustainability. However, the current data science applications in the mining industry are mostly noncomprehensive, especially inadequate in evaluations, thus often requiring further study to be potentially beneficial to operations. Furthermore, it was found that existing literature paid limited attention to understanding the role of such techniques. Hence, in this paper we aim to build an end-to-end machine learning powered data-driven framework for intelligent geo-hazard analytics to support decision-making for underground mining data management, where multiple types of data are managed in an integrated database to support the unified machine-learning model. Here we present the framework as data-driven workflow processes, including data gathering, data preparation, data processing and data presentation. In addition, we present an application scenario of the proposed framework, where falls of ground (FoG) is managed with the historical FoG investigation reports, related panel hazard ratings, compliance data and rock mass characteristics. A demonstration can be dynamic forecasting of high-risk areas for FoG based on both spatial and temporal factors, including a 3D data visualisation. Such a scenario shows the potential of the proposed framework to establish connections among various data fields across a diverse category of data. Furthermore, the results offer important insights for ground instability management and can potentially optimise the underground operation flow.

Nov 29, 2022

By R Paterson, A Christensen

The routine use of gravity gradiometry for the detection of orebodies with no outcrop is now being undertaken. The commodities and orebody styles range from banded iron ore formations to volcanogenic massive sulfide (VMS) style polymetallic deposits. This recent innovation of flying gravity gradiometry was pioneered by BHP Billiton and Lockheed Martin with the Falcon technology (Lee, 2001), and now two additional systems, also using Lockheed Martin instruments, are deployed. In South Africa, magnetic gradiometry is being developed and deployed with the same objectives in mind. In this case, a system from Institute of Photonic Technology (IPHT) is being used. The detectable wavelengths from such systems have decreased to less than 200 m in the last year, and it is expected in 2011 that wavelengths to less than 100 m, with anomaly signal strengths of less than 2 Eotvos for gravity gradiometry will be viable. The key to these advances lies in the improvements of processing software and geological modelling. In particular, methods using all the tensor components are starting to be routinely deployed to filter, level and grid the observed signal. These methods do, however, require full insight and understanding of the reference coordinate systems used by the various instrument designers and survey operators. The digital terrain models need also to be observed to an accuracy of better than 20 m cell sizes, using such techniques as Lidar. Then the terrain effects can be modelled. The topographic surface represents the largest and most proximal density contrast encountered in an airborne survey. Hence terrain effects can have significant impact on airborne gravity gradiometry data. A decorrelation of the terrain effect with the observed signal requires a method of best fitting with a regional surface density. A novel technique has been developed for this purpose. This technique uses a tensor algebra to estimate a density between 1 - 4 g/cc that explains the average observed signal. Armed with this result, the anomalous buried bodies can be revealed by subtraction.

Sep 26, 2011

By H von Blottnitz, A C. Keith

The influence of the life of a mine extends beyond its immediate vicinity both in geographic and temporal terms. Decisions around mine approvals are generally made based on economics, for the mine owner and immediate environmental and social impacts by governments and communities. The value from life-of-mine planning can also be viewed in a holistic frame across the entire value chain from mine to product user. This research examines the Carmichael Coal Mine in light of the holistic benefits and impacts along its value chain from the mine to relieving the lot of energy poor in India.CITATION:Keith, A C and von Blottnitz, H, 2016. Can Australian coal alleviate energy poverty in India – a case study, in Proceedings Life-of-Mine 2016 Conference , pp 52–56 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By J J. Van Wijk, A R. Penney

Successful management of geotechnical risk at a mining operation is more than just having a good ground control management plan or using advanced numerical modelling and the latest monitoring technologies. The fundamental requirements for effective geotechnical risk management include identification of potential failure modes, identifying and implementing appropriate controls, and demonstrating the effectiveness of those controls. Effective geotechnical risk management requires an integrated approach by confirming that appropriate risk management systems have been identified and implemented (management plans, procedures etc), and that these systems are executed consistently in the field across all working areas. Development of a thorough integrated auditing process executed by an experienced team of technical subject matter experts with substantial operational knowledge, provides a more complete picture of catastrophic hazard management. Following consistent evaluation criteria allows benchmarking of systems and implementation compliance between the sites being audited, and the results can then be ranked against other operations in an industry database.

Nov 29, 2022

By A Kleinitz, J Halilovic, K Trappitt

Mine operators use grade control to determine the destination of each block of material in the mine. In polymetallic mines, grades are best expressed in dollars: the Net Smelter Return, NSR, per tonne. To estimate NSRs, geologists working on grade control develop models for each geometallurgical domain in the mine. These models may incorporate observations on the mineralogy and grain sizes of the material being examined. The site’s mill operators contribute to the models by providing geologists with statistical analyses that relate assay results and mineralogical compositions to metallurgical parameters, such as the rates of recovery of each economic metal to each of the concentrates produced, and the compositions of those concentrates. The team responsible for sales and marketing of the site’s products contributes to the NSR models by providing details of the costs of shipping concentrates to smelters and refineries; and by providing figures that are specified in the smelter contracts, such as the payability of the metals in each concentrate and the fees charged by the smelter. The mill operators also provide, for the NSR models, equations to estimate the rates of recovery of deleterious materials to each concentrate. Deleterious materials comprise mostly halogens and amphoteric elements, both of which reduce the efficiency of smelters. Furthermore, deleterious materials such as antimony and arsenic may be poisonous to people and to the environment. The sales and marketing team provide specifics of the penalties that smelters impose upon deleterious materials. These penalties may reduce NSRs by tens of percent, possibly to levels below the cut-off grade. Thus, in the blocks that are subject to grade control, mine geologists monitor not only the concentrations of economic metals, but also the presence and abundance of deleterious materials. The preparation and maintenance of models, to estimate NSRs and to assess changes in the levels of potentially toxic materials to be mined, requires close and continuing consultation between corporate departments. There must be strong communication of mine geologists with the mill operators; with the people who market the mine’s concentrates; and, should there be a risk of encountering toxic levels of deleterious materials, with the mine’s health, safety and environmental officers. This co-operation could require radical changes in the structure of many organisations. However, experience suggests that such changes can significantly improve the profitability of a mine.

Mar 22, 2022

By J Furtney, W Fu, D Nutakor, A Brose

Rock blasting outcomes are often a shared responsibility of both the mine operations group and the mine geotechnical group. From an operational logistics and planning perspective, blasting concerns include optimal fragmentation for subsequent crushing, ensuring the blast is energetic enough to allow easy digging, and understanding the effect of muck from a previous blast on the current blast. From a geotechnical perspective, wall damage and catch bench capacity are the primary concerns. Other concerns for both teams include damage to mine infrastructure by fly rock or blast-induced vibrations, and the stability of open stopes under the pit. This work presents two blast modelling applications (or ‘apps’). The basic app instantly gives fragmentation and wall damage predictions for a given generic blast design. The advanced app loads the current pit contours, reads the blast design from a spreadsheet, and calculates the expected vibration magnitude and peak frequency. The apps have been developed specifically for the Rio Tinto Borates and Lithium Mine in California and are used to support blast design between the operations group and geotechnical group. The basic app instantly gives fragmentation and vibration predictions given a blast design by combining the Kuz-Ram fragmentation model with the scaled distance model for vibrations. The advanced app uses the signature hole method. Blasting outcomes at the mine have improved since using the apps.

Jun 22, 2022

By C Linklater, A Garvie, D Kentwell

Various Australian and international regulatory bodies (Environmental Protection Authority, 2015) require an early assessment of the geochemistry of waste rock. This usually includes estimates of the locations and volumes of potentially acid forming (PAF) materials and requires sampling of the waste rock zones as well as submitting the samples for a series of tests. We know that the required number of samples will vary depending on rock type, mean sulfur levels and spatial variability of sulfur as well as total volume. The key question is how do we know when we have enough samples?This extended abstract describes the application of geostatistical methods to examine how sample numbers and sample locations influence the preliminary conclusions that may be drawn for early stage waste characterisation.CITATION:Kentwell, D, Garvie, A and Linklater, C, 2016. Geostatistics and sample numbers from an acid and metalliferous drainage perspective, in Proceedings Life-of-Mine 2016 Conference , pp 12–15 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

The Operation of the LAROX PF-50 Pressure Filter at 'Ellatzite-Med' Flotation Plant, Bulgaria The implementation of Larox pressure belt filter, type Larox PF-50 provided within 6˜8% moisture content of the produced copper concentrate, which allowed good market realisation. The start-up of the pressure filter in 2009 reduced the electricity costs several times and had a positive impact on the technological regime of flotation. This article reveals the investigation results from the operation of the pressure filter according to different situations (density of the pulp, time for filtration, pressure of the material, pressure of the drying air, time for drying with air and other factors). The investment made in the pressure filter application is a guarantee for the successful operation of 'Ellatzite' flotation plant, Bulgaria in the coming years.

Sep 13, 2010

By A Mcquillan, N Bar

Geotechnical models developed during the open pit mine planning stage are generally three-dimensional (3D) in component to capture the spatial variation in geological, structural, hydrogeological and geomechanical conditions. Yet when geotechnical analysis is completed, often the 3D geological, hydrogeological and structural models are simplified to two-dimensions (2D). This paper demonstrates this simplification, through referenced case studies, can lead to the wrong failure mechanism being analysed and/or a conservative Factor of Safety (FOS), or Strength Reduction Factor (SRF), being calculated, leading to a false sense of stability. There exists a paradigm that the FOS calculated using 2D limit equilibrium (LE), or the Strength Reduction Factor (SRF) calculated using 2D finite element (FE), modelling methods is generally conservative, ie lower, than the true FOS. However, this assumption that 3D FOS, or 3D SRF, is always higher than 2D FOS, or 2D SRF, is not always correct (Chen and Chameau, 1983; Bromhead and Martin, 2004; Herza et al, 2017; Pyke, 2017; Dana et al, 2018).

Nov 29, 2022

By M D. Goodz

MacPhersons Reward gold deposit is in a post-kinematic tonalite intrusion which is a setting different from many other deposits of the Coolgardie goldfield that are hosted in early Archaean tholeiitic sills or meta-sedimentary rocks. Gold mineralisation at MacPhersons Reward consists of auriferous quartz veins that are best developed in the tonalite but extend to the adjacent komatiitic rocks and along the lithological contact zones. The gold-related alteration halo is dominated by biotite-chlorite and pyrrhotite. Unlike many other Coolgardie deposits, the As concentrations are low.

Aug 22, 2011

By A Melloy, D Holt, M Jurak

Oaky North is AustraliaÆs highest producing underground coal mine. In 2011, the mine produced 8.7 Mt of high-quality coking coal. The high quantities are a result of the constant strive for optimising the operating time of major production units, which involves investing numerous resources, including diesel equipment, in supporting and maintaining their operation.In July 2011 it was identified that the diesel particulate matter (DPM) levels in the underground workings were above acceptable levels, due to the high level of diesel activity. Over the next 12 months, several controls were implemented to reduce exposure to personnel: the main ventilation system was upgraded; the production forecast was adjusted to better manage the diesel fleet, removing surges in diesel usage; and an electronic diesel tag board was introduced to centrally manage the distribution of diesel usage around the mine.From the start of the campaign in emission reduction, an intense DPM monitoring regime was established. Within a few months of the introduction of the centralised tag board, there was a major reduction in emission levels. After the installation and commissioning of the new main fans, the emission levels dropped further, such that over-exposures are now a rarity.Oaky North continues to explore new systems to better utilise their diesel fleet while still maintaining control over DPM emissions.CITATION:Melloy, A, Holt, D and Jurak, M, 2013. Reduction in diesel particulate matter at Oaky North, in Proceedings The Australian Mine Ventilation Conference , pp 187-190 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By D Olwagen, C Stanton, J Gerber

From December 2013 to February 2014 the Southern Middleback Ranges magnetite concentrator went through a successful optimisation process that included the installation of extra grinding power to treat a wider range of ore types. After the initial improvements, sampling surveys were conducted to identify the mineral deportment through the concentrator. Samples collected during the survey were analysed using X-ray fluorescence, quantitative X-ray diffraction and QEMSCAN™ to cross-validate the analysis. Certain streams were also put through a laboratory-scale Davis Tube Recovery washing process to produce clean concentrates for analysis. The QEMSCAN™ analysis identified various metallurgical characteristics (mineral association, particle sizes, grain sizes, particle densities, etc) and these were evaluated for each separation and comminution stage to both understand the processes involved and identify opportunities for improvement. Key findings from the investigation indicated the importance of understanding the elemental deportment of target elements throughout the various minerals. The standard practice of tracking iron deportment through assay provided misleading results on losses to tail through the plant. The investigation provided insight into both wanted and unwanted minerals and the efficiency of each separation stage. The efficiencies of separation are critical due to their impact on downstream capacity, and the investigation provided insight into where opportunities exist to extract more benefit. The findings of the geometallurgical analysis have been implemented on the concentrator, and improvements in the rejection of non-magnetic minerals have been seen.CITATION:Gerber, J, Stanton, C and Olwagen, D, 2015. Using geometallurgy during process optimisation activities at the Southern Middleback Ranges magnetite concentrator, in Proceedings Iron Ore 2015, pp 561–566 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By R Marchant, D Willingham

"Predictive maintenance (also known as PHM or equipment ‘health monitoring’) refers to the intelligent monitoring of equipment to avoid future equipment failures. In contrast to conventional preventive maintenance, the maintenance schedule is not determined by a prescribed timeline; instead, it is determined by analytic algorithms, such as machine learning, using data collected from equipment sensors and/or via simulation.Predictive maintenance offers the following benefits for operators and equipment manufacturers:reduction of equipment downtime by identifying issues before failure, thereby enabling convenient scheduling of equipment service and extending equipment lifetimeautomatic determination of the root cause of the failure, enabling appropriate service to be performed without utilising resources to determine a diagnosis avoidance of costs of unnecessary maintenance and unexpected failures improved safety and product quality.Algorithms and data are critical to predictive maintenance success. Sensor data preprocessing is performed using advanced statistical and signal processing techniques. In the case that data isn’t available for the full range of operating modes, operating scenarios can be simulated. Machine learning techniques are then used to estimate equipment health. Once tested, predictive maintenance algorithms may be operationalised in an IT environment such as a server or cloud. Alternatively, algorithms may be implemented in an embedded system directly on the equipment, allowing for faster response times and significantly reducing the amount of data sent over the network.In this paper, we use both historical and simulated data of the plant under various modes of operation including run to failure, and we then leverage machine learning techniques in MATLAB to estimate degradation and remaining useful life. This technique, of combining both simulation models and machine learning, in the areas of predictive maintenance and equipment health monitoring has been adopted by Safran, makers of aircraft jet engines, since 2007. They now have over 160 modules developed (Lacaille and Aurelie, 2015).Citation:Willingham, D and Marchant, R, 2016. Predictive Maintenance Using Simulation and Machine Learning, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 279–284 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By G Chitumbura

Raise boring is a critical aspect of mining at Xstrata Copper’s Mount Isa Copper Operations (MICO). MICO’s internal raise boring department regularly develops ventilation rises, orepasses and stope cut-off rises and reams approximately 2500 m per annum. Developed, trialled and implemented as standard practice over the past two years, procedural changes in constructing the raise bore machine’s foundations have significantly reduced operator exposure to raise boring’s inherent risks of working around open holes and manual handling. An additional cost benefit of this newly-adopted procedure is derived from reducing the likelihood of damaging the machine while de-rigging.When conforming to standard industry raise boring practices, exposure to an open hole begins when the reamer breaks through the concrete pad and ends when it is removed from the hole – a process which, depending on the size of the hole and the raise boring machine, can take up to three days to complete. Although wearing fall restraint equipment, operators working on and around the raise bore machine during de-rigging are continually exposed to the risk of falling from heights. In contrast, MICO’s newly-developed and successfully-implemented presink raise boring system reduces this exposure to a maximum of four hours, regardless of hole size. Exposure to manual handling hazards is also substantially reduced as the presink procedure eliminates manual placement of a 100 kg drill bit under the machine to commence pilot-hole drilling. Outcomes of implementing the presink System at MICO have been so beneficial that it is now standard procedure for all reaming in excess of 1 m diameters.

Mar 21, 2011

By D Gerrard, J Begelhole, J Gerber

The Iron Magnet deposit has been mined since 2007 when Arrium (then OneSteel) commissioned the magnetite concentrator to supply feed to the pelletising plant in Whyalla. The concentrate quality requirement for the customer required consistent product with minimal variability. In the early stages of operation, it was identified that the feed variability introduced significant changes in the concentrate quality, which was outside the acceptable customer limits.In 2011, a geometallurgical regression model was developed that allowed for the estimation of concentrate quality produced from the feed material. This was based on a laboratory-scale Davis Tube Recovery (DTR) test performed on the feed material. The objective of the project was to characterise the raw ore in the pit to allow for blending prior to crushing. By blending the feed to the concentrator, minimal concentrate quality variation within the plant was achieved. The orebody was divided into geometallurgical classes, called ore types, based on the mineral texture and magnetic mass recovery. Each geometallurgical class consisted of material with similar metallurgical performances. For each individual blast pattern, the ore was grouped into the geometallurgical classes and a composite sample was created. The composite sample was put through the laboratory-scale DTR test and the results were used to estimate the metallurgical performance of the material.The characterisation process and feed pile build methodology was applied in early 2013 and went through an optimisation and streamlining phase. Since the implementation of the geometallurgical characterisation process, the plant has seen a significant reduction in concentrate variability and measurable throughput gains. The characterisation process has also increased the amount of material that is now classified as ore.CITATION:Gerber, J, Gerrard, D and Begelhole, J, 2015. Geometallurgy of the South Middleback Ranges magnetite deposit – predicting plant performance from the pit, in Proceedings Iron Ore 2015, pp 555–560 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

The optimisation and validation of shearer cutting methods is a time consuming engineering task. Many different parameters, of which not all can be controlled, can vary. The easiest solution, to increase the installed power and the longwall length, is not always the best. A different cutting method can increase the capacity without the need of new machines. The Department for Mining and Metallurgy Machinery at RWTH Aachen University therefore developed ProSL, the simulation tool for shearer and longwall operations. ProSL enables the engineer to create his own cutting methods and compare it with other methods. Machine-data can easily be varied to see the impact on the method. The research shows that sophisticated longwall methods increase the productivity of the system. The paper presents the results of the calculation with ProSL and shows how higher efficiency and lower costs can be achieved.

Dec 6, 2010

By G Collecutt, D Proud, D Humphreys

"The hazards associated with dust explosions are well known, and coal dust explosions present a significant hazard in the underground coal mining industry worldwide. In earlier work, we presented computational fluid dynamics (CFD) simulations and test results for coal dust explosions within a 2.5 m diameter circular gallery, along with CFD simulations and test results for the suppression of these explosions with finely atomised water sprays. In this paper, we present refinements to the CFD modelling that yield a significantly improved calibration with the test results, and proceed to investigate by CFD the requirements for suppression of a coal dust explosion in a typical underground roadway. This work was carried out under an ACARP project and we gratefully acknowledge their assistance. CITATION: Proud, D, Collecutt, G and Humphreys, D, 2015. Computational fluid dynamics modelling of coal dust explosions and suppression systems, in Proceedings The Australian Mine Ventilation Conference, pp 309–314 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 31, 2015