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By P Thompson, D Rose, S Yu, W Baum, R Zahn, D Meadows, G Hall

Opportunities to improve mill operations are often cited by mining companies and recognised in many concentrators spread throughout the world but are not always followed through. Copper-molybdenum concentrator operations are challenged by a continuously increasing list of detrimental factors. They include deteriorating ore characteristics and poor mineralogical information on deeper ores, water quality and availability, steel wear and increasing power costs. Rapidly declining productivity, sustainability and environmental factors, new taxes, mining industry global skill set shortages, to name but a few, must also be considered. The days of maximising value by just increasing production or simple cost cutting are fading and will not be sufficient for the future of more complex mineral processing operations and larger plants. As a result, FLSmidth’s Global Process Technology Group has launched a plant and process optimisation program based on mineralogical and metallurgical surveys.Copper-molybdenum concentrators of the future need a paradigm shift. Modelling and simulation tools alone are not the answer to complex mineralogical associations and larger scale equipment and operations. Detailed area by area review aimed at identifying process constraints in terms of equipment and operating practice in conjunction with robust diagnostic work, ie mineralogical and metallurgical characterisation, are mandatory for process optimisation. The navigational beacon, for all operations who want to remain competitive, will be ‘process efficiency’. Since the use of automated mineral analysers has become more readily available and reliable, mineralogical-metallurgical plant surveys have proven themselves as the most efficient tool for optimising plant performance.The following paper will illustrate how operations can move toward eliminating under-performing flow sheets, fixing run-away flotation conditions, maximising individual process equipment performance, preventing shortcuts in Bond work index testing which may cause the failure of comminution models and minimising costly and time-consuming ‘debottlenecking’. As previous plant surveys have shown, the net project cash flow can be increased by 50 to 200 per cent if a combination of robust ore characterisation and plant process mineralogy is performed. The combined plant survey approach has been demonstrated successfully in a multitude of operations. This includes the use of key ore types in concert with statistically sampled process streams, bench-scale metallurgical tests and automated mineral analysis on a size-by-size basis.CITATION:Meadows, D, Hall, G, Rose, D, Thompson, P, Baum, W, Zahn, R and Yu, S, 2014. Copper-molybdenum concentrator surveys using mineralogy and process benchmarking tools to improve overall plant performance, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 315–322 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By G Clarke

Commissioning of the Cannington processing plant began in October 1997. The nameplate capacity (of 1.55 million tonnes of ore per annum) was achieved relatively quickly. Since then (like many mines) the operation has strived to increase throughput and improve valuable metal recoveries, to offset declining head grades and lift the value of the operation. The processing plant now has the capability of treating over 3.2 million tonnes of ore per annum and in financial year 2005/06 the combined concentrate production exceeded 600 000 wet tonnes, approximately 80 per cent above concentrate output in the first full year of operation (at the design feed rate). This improved performance was achieved by making changes and additions to each of the major unit processes û primary grinding, flotation, leaching, filtering and paste fill preparation. The changes have included: adding a fines flotation circuit, expanding the grinding circuit, adding a pebble crusher, switching from continuous to batch leaching, building paste conveyors and decommissioning the column flotation cleaning circuits. This paper reviews these changes, outlines the current operating practices and discusses the challenges or opportunities that remain.

Jan 1, 2007

By K Williams, M Pender, T Honeyands, T Krull, D McCallum, R Holmes, R Orense

Bulk cargoes, including iron ore fines, must be shipped according to the rules agreed by the member states of the International Maritime Organization (IMO). One critical safety measure is the transportable moisture limit (T?ML) required for Group A cargoes (cargoes that may liquefy). A number of shipping incidents involving iron ore fines from India, where liquefaction of the cargo was suspected to be the cause, have brought the issue of iron ore fines T?ML into the spotlight. Extensive research has been undertaken by the major iron ore producers from Australia and Brazil to support the IMO in developing regulations for the shipment of iron ore fines. To this end, iron ore companies sponsored the AMIRA P1097 project to establish a modified T?ML test approach specific to iron ore fines. The project was undertaken by TUNRA Bulk Solids, CSIRO’s Centre for Bulk Solids and Particulate Technology and the University of Auckland, with project leadership provided by Creative Process Innovation. This program of work supported test work findings from the IMO Iron Ore Technical Working Group, which reported its findings in September 2013.The purpose of this paper is to present the major research findings from the AMIRA P1097 project, which includes a review of the original T?ML methods, highlights of the research that supported the new iron ore fines T?ML method and an outline of current iron ore T?ML requirements.CITATION:Williams, K, Honeyands, T, Holmes, R, Orense, R, Roberts, A, Pender, M, McCallum, D and Krull, T, 2015. Maritime bulk cargo transportable moisture limit requirements for iron ore shipments, in Proceedings Iron Ore 2015, pp 399–410 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By S B. Fitch, S A. Wilson, A J. R Barr, P R. Searle

Improving the safety culture and performance of any operation is a fundamental goal of every mine operator. Methods of implementing, or changing a culture have developed from the early methods of operant conditioning, for example rewarding crews for achieving nominated safety milestones i.e. 3 months Lost Time Injury (LTI) free through to the current model of engaging a workforce through education and empowerment. As a large scale and mature operation with multiple contractors, Telfer has been exposed to numerous programs throughout its history. This has provided the opportunity to build on and complement these systems by integrating key elements from each. SAFE 360° is a new approach developed to engage the workforce in a holistic approach to encourage positive behaviours across all facets of an individual’s life which results in a focus on situational awareness at all times, rather than being workplace specific. It is based on three key modules: • Emotional Intelligence • Mindfulness • Situational Awareness Each module has a series of modules that help enhance the individual’s sense of self, leading to an ability to self-reflect and self-manage whilst empowering them with the moral courage to challenge their peers to raise standards. Since commencing this SAFE 360° behavioural safety risk management journey in November 2017, we have witnessed a change in the way our workforce engages with each other, their workplace and with management. There has been an increase in hazard perception, identification and ownership of issues, and we have seen a significant decrease in site TRIFR rate from 13.7 to 5.7 (as of April 2019). This paper will provide an overview of the program, how it has been implemented, case studies to demonstrate outcomes and KPIs used to measure effectiveness.

Mar 15, 2021

By S Mundell, A Atkins, S van de Water

Geoscientific information management enables the capture, management and delivery of the original geoscientific observations and measurements of the earth’s natural resources. However, original observations and measurements are worth nothing if the quality and integrity of the data can’t be guaranteed. Geoscientific information is one of the fundamental assets enabling miners to make confident and accurate business decisions, whether that is defining a resource model, performing reconciliation, delivering ore reserve reports or meeting environmental compliance requirements. Without access to reliable, validated or verified data it increases the risk of miners using incorrect information for reporting and compliance. Industry codes, such as JORC, or government regulations, such as environmental compliance requirements, must be adhered to and companies should be able to confidently report to these standards. Without having a robust information management framework in place, it becomes a challenge to make trustworthy decisions, report confidently and reduce the risk of non-compliance. As a key initiative, good data governance should form one part of a miner’s information management strategy. Within the mining industry it is common for companies to only consider technology tools as the key focus for compliance whereas a mature information management focus will additionally consider people and process. All three pillars are critical for a miner to have confidence in their data driven decisions. This paper discusses an industry framework for best-practice geoscientific information management based on the observations gathered from analysing data management practices within the mining industry. It focuses on how the three pillars of people, process and technology are crucial elements to improve operational decisions and ensure companies are compliant.

Nov 8, 2021

By P Luo, J E. Danoczi, P Nakutnyy

Sensor-based sorting methods to remove waste or for upgrading ore prior to downstream metallurgical processing is becoming more prevalent for mining operations. X-ray transmission (XRT) sorters are a popular choice for mineral processing plants since they can sort a wide variety of minerals. XRT sorters pass high intensity X-rays through particles to generate images of varying greyscale, based on their effective atomic density. The ore sorter then mechanically separates the particles using algorithms based on the images. A popular test currently used to evaluate the amenability of the ore to XRT sorting is to pass the particles through the sorter and obtain the greyscale images showing mineralogical differences. This test provides information on the mineralogical heterogeneity between ore particles for their separation. However, it does not provide an understanding of the actual mineralogical composition of the ore or information pertaining to which other minerals may respond in a similar manner, nor does it provide liberation information. This paper describes a test that combines high resolution X-ray micro Computer Tomography (CT) combined with QEMScan to obtain information about amenability of ore to XRT sorting and to obtain valuable information that can streamline metallurgical testwork programs. This test also provides information relating to particle thickness and associated X-ray attenuation coefficients, desired mineral presence and mineralogical information relating to associated minerals and clays to assist with developing sorting algorithms. Combining the CT and QEMScan can address many limitations of the current method to determine whether XRT sorting technology is appropriate for particular ores. Mineralogy information from QEMScan can identify incidences of; mineral encapsulation, problematic clays, detrimental minerals as well as calibrate the greyscale values of CT data. Additional 3D CT imaging carried out on cores provides spatial information of the minerals within the ore and mineral grades.

Nov 10, 2020

By J Morgan

Regular monitoring of surface deformation over mine sites is important for providing updated information to managers regarding geotechnical risks related to ground instabilities. This is particularly true in cases where unexpected or accelerating movement patterns are observed, as these trends may have implications related to worker safety within active mining environments, as well as continuity of ongoing operations. InSAR is an active remote sensing technique that uses radar satellite imagery to precisely measure ground movement. This technology has started to become a standard tool for monitoring surface stability in many different sectors, including underground and open pit/cut mining applications. In recent years the launch of satellites that collect radar imagery on a more frequent basis, coupled with advances in InSAR processing techniques, has improved both the extent to which movement patterns typical of mining operations can be characterized and the temporal scale on which results can be reported to geotechnical departments. As a result of these developments, InSAR monitoring can now better meet the operational needs of mine sites. An overview of the more recently launched satellites that have a particular relevance to the monitoring of mines is provided, along with an explanation of the InSAR tools that are the most valuable to mine managers and geotechnical engineers. First, broad differences between high resolution X-band imagery and low resolution (but freely available) Sentinel imagery are discussed. Second, the various InSAR tools and their particular applications for different types of mine sites and operations are covered, which include fast delivery deformation maps for short-term reporting, multi-interferometric algorithms for longer-term analyses and rapid movement tracking (RMT) for emergency monitoring or high-risk situations. The ability of the technology to resolve 2D and 3D movement is also touched upon. Practical examples of InSAR application over a variety of mine sites will be presented, as well as surrounding hazards including landslides, to illustrate how InSAR can help provide geotechnical engineers with a picture of surface stability over the full mine site and surrounding areas to help manage risk. CITATION:Morgan, J, 2018. Wide area mapping of ground instabilities from space: InSAR for geotechnical risk assessment and hazard monitoring, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 375–382 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

At Cliffs Natural Resources Ltd (CNR) crushing and shipping sample stations, precisions are estimated for the sampling, preparation and measurement stages of iron ore sampling in accordance with ISO 3085 (2002). In this Standard, gross duplicate samples are prepared at each of the three stages, yielding eight measurement assays. Appropriate calculations of the differences between assay pairs are then made to estimate precision of each stage of sampling. The International Standard for checking precision in iron ore sampling, ISO 3085 (2002) prescribes a method for identifying outliers that is ambiguous and possibly inappropriate. The procedure also makes an unnecessary implicit assumption, that the differences between assay pairs are normally distributed. The Anderson-Darling statistic is used to demonstrate that in some cases the assay pair differences have distributions significantly different from normal. When applied at CNR as specified, the Standard leads to precision estimates well below the expected values, thus overestimating the sampling method's capability and limiting the opportunity for real process improvement. This paper suggests an improved method of estimating sampling, preparation and measurement precision. A bootstrap procedure is used to estimate confidence limits for the calculated precision estimates. The proposed method would be suitable for testing blasthole precision. The discussion is supported by extensive simulation modelling of realistic data.

Mar 1, 2010

By T Elms, R Beckman, M Sampson

"In today’s mining industry, the pressure of reducing costs and increasing production while maintaining high safety standards is at the forefront of operational endeavours. A combination of specific mining knowledge and technological advances has helped enable this notion. Fleet management systems have been developed to enable sites to better measure and manage production to improve operational efficiency.The integral part to managing production is having accurate, readily accessible data. This empowers key stakeholders in the management team to drive production reporting, materials tracking and budget forecasting.If a site does not run a fleet management system, manual input is heavily relied upon for production data, which introduces increased risk of human input error. Errors can drive outcomes that don’t achieve increased production at a reduced cost. Alternatively, a fleet management system can have improved accuracy but involves a high monetary investment. Such an investment is not always feasible for smaller mining operations subject to current industry cost pressures.The Emeco Operating System has been developed in alliance with sites such as the Mungari White Foil Operations by satisfying the criteria of a low intensity hardware installation, material tracking data validation processes, remote monitoring, identification of metrics to improve overall operating efficiency and providing the right information to key stakeholders.Citation:Beckman, R, Elms, T and Sampson, M, 2016. Getting Accurate Mine Information to the Right Teams to Drive Production Improvement, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 203–211 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By N Anderson

With traditional grade control processes, geological models are created by geologists at the completion of the data collection stage and wireframe construction is closed off at a set date to allow for time to complete the estimation process. Any issues identified at earlier stages or the addition of new data requires the estimation process to be started again. Alternative interpretations are explored only if time allows and often in a limited fashion. An alternative workflow has been developed at the Waihi Underground Gold Mine utilising Leapfrog Edge and Seequent Central. Geological and grade control models are created, dynamically linked, and saved as separate branches. A project geologist is able to work on the grade control model and a mine geologist on the geological model simultaneously. This allows for a non-linear modelling workflow with continual review and feedback. The introduction of new data can occur right up to the model due date, with data collection, validation, alternate interpretation, and review happening incrementally. Models are categorised and stored in Seequent Central according to project status. An approved version of the geological model and grade control estimate are uploaded at the time of release and transparently capture all data used at a point in time, as well as the review process. Dynamically updating models for grade control has reduced turnaround time while increasing accuracy and quality. Estimates of individual domains are vastly improved from being able to rapidly evaluate the effects of model parameter changes in real time and 3D. Development and stope design directly benefit from these streamlined processes, with higher quality, timely production occurring as a result.

Mar 22, 2022

By P Mikula, B Darlington, J Graham, P Young

In underground mines experiencing dynamic events, there is an ever-present challenge to design and maintain a capable ground support system. One key component of ground support systems is surface support, which serves the essential roles of retaining failed rock and transferring forces generated by surface displacement to rock bolts or other support elements. Observations underground show that in many instances, standard mesh panels alone do not provide sufficient dynamic support to retain substantial bulking failures imposing displacement onto mesh, and in such cases Mesh straps and W-straps may be employed. Determining the performance of surface support elements proves to be difficult, with a multitude of variables at play in the underground environment. Quite comprehensive work has been completed on laboratory testing of surface support systems; however, very little work has been conducted on in situ dynamic testing of Mesh straps and W-straps. In 2019 in Western Area’s Flying Fox Mine, in situ dynamic testing was conducted on a series of Mesh straps and W-straps using Sandvik’s in situ Dynamic Test Rig (DTR). The testing regime applied impact energies from 5.1 to 15.3 kJ to Mesh straps and W-straps. The performance of the straps that did not fail was a maximum absorbed energy of 9.3 kJ and 14.2 kJ for the Mesh straps and W-straps respectively. The testing successfully demonstrated the ability of Sandvik’s DTR to test not only rock bolts, but also surface support elements, creating new testing and research possibilities. The testing also provided important design guidance data that is not practicable to obtain using laboratory dynamic testing facilities.

Nov 29, 2022

By I Douglas, L Allen

Localised indicator kriging was developed following a similar approach used by Marat Abzalov (2006) in his paper titled æLocalised uniform conditioning (LUC): A new approach for direct modelling of small blocksÆ. Abzalov introduced the idea of mapping panel distributions from uniform conditioning onto selective mining unit-sized blocks that were created using ordinary kriging. This concept of remapping panel distributions was applied to multiple indicator kriging histograms.At Newmont a program was developed that made the remapping of MIK histograms to SMU sized blocks extremely efficient and was subsequently tested on several gold deposits. The results have been encouraging as the localised indicator kriging (LIK) method has eliminated many issues that have plagued both ordinary kriging and multiple indicator kriging. Use of localised indicator kriging methodology limits the smearing of high-grade and the over-smoothing of grade that is common and difficult to control in OK but retains the ability for localising grades. LIK also simplifies change-of-support corrections, eliminates un-mineable slivers of low or high-grade when dealing with small tonnages, and allows for the mapping of linear and non-linear estimates into the same block.

Sep 26, 2011

By Q Shu, T Deng, B Yan, B Song, D Wang

In view of the lack of phase equilibria data of vanadium-bearing oxide system and the desirability of them for design or optimisation of vanadium extraction process, the phase equilibria relationships of V2O3-FeO-SiO2-CaO(15 mass per cent) system were determined experimentally and then an isothermal section phase diagram of this system was constructed. Totally, 81 samples of different composition were equilibrated at 1623 K for 48 hours in iron crucible under Ar atmosphere. The equilibrated samples were quenched quickly in cold water, and then the phase constituents of all the samples were identified by X-ray diffraction (XRD) combined with electron probe microanalysis (EPMA) measurements.

Aug 21, 2024

By G Pattenden, R Hargreaves, P Pettit

"Even with the cyclic nature of mining, when it comes down to it, the bottom line is that whatever direction the commodity market is going there is always a desire to improve the economics of an operation in order to deliver a greater return to investors. Adapting to market pressures by introduction of an operational process change can often have a downstream impact. What may be less obvious is that reconciliation can play an important part in measuring the effectiveness of many operational changes. Through the adoption of best practice reconciliation and related comparisons, it is possible to measure the impact of changes across the mine value chain and identify variability that may have been introduced. Using analytical business improvement tools, examining and monitoring planned changes can be crucial in understanding whether the introduced changes have been effective and whether they have provided the expected result. Using several case studies, the authors will highlight the benefits provided by modern business intelligence tools, which can provide data validation and accurately report data trends related to both planned and unplanned change events.Citation:Hargreaves, R, Pattenden, G and Pettit, P, 2016. Measuring the Effectiveness of Change through Best Practice Reconciliation, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 71–83 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By J Stipcevich, N Patel, J Faithful5, S Narendranathan, L Tatnell4

ENGIE, the current owner and operator of the Hazelwood Open Cut coalmine, are in the process of rehabilitating the mine site in preparation for mine closure. Bucket wheel excavators (dredgers) used during coal mining operations are in the process of being demolished, which involves the controlled felling of dredger components using explosives. With the mine located in close proximity to the Morwell township and other critical public infrastructure, it is crucial that the use of explosives and the possible implications for mine stability is well understood. The felling of Large Mining Equipment (LME) will apply an impact load immediately to the underlying coal benches with the adjacent coal batters potentially at risk also of adverse slope stability impacts. This paper presents the 3D stability modelling methods employed to successfully assess the potentially adverse stability implications associated with LME collapse.

Jun 21, 2022

By T McLeod, B Catto

AngloGold Ashanti Australia’s (AGAA) Tropicana gold mine (TGM) geology department seized the rare opportunity of building a new geology department for a new operation: the philosophy, the people and the processes. Not satisfied with the status quo, or simply repeating what was familiar and already known, the vision was for an innovative, agile, multidiscipline, high performance team, capable of delivering on expectations.To achieve this, the geology department has operationalised key components of human resource management (HRM).This paper describes the operational design and implementation of key HRM components: job analysis, organisational design and organisational development. The benefits of this approach are presented in terms of engagement and autonomy in roles, opportunity for role variety and flexibility of the organisational structure. The result is a geology department that provides the functions of mine geology, resource development, regional exploration, survey, data management, geographic information systems (GIS), resource modelling, scheduling, sample preparation, resource coordination and hydrogeology, and even geotechnical engineering for a year!Considerations for application in other geology departments are presented in terms of fundamental requirements and lessons learnt. Fundamental requirements for success have been the sustained support of the general manager, valuing the scrutiny that comes with continuous improvement, high quality HRM systems and tools within the organisation, and a committed leadership group within the department. One of the most important lessons learnt is that a robust process of ‘induction to role’ is critical – the process of familiarising new starters with who we are and the way we work.CITATION:Catto, B and McLeod, T, 2017. Rewriting the rule book – geology organisational design, in Proceedings Tenth International Mining Geology Conference 2017, pp 137–142 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

The Australasian Institute of Mining and Metallurgy (AusIMM) is a professional society for all those associated with the activities of the mineral industry. Differences of opinion exist within the membership of the AusIMM on the role it should play in the future as a professional society in a changing industry and world environment. This same dilemma is concerning other professional societies of which the author is a member. Some of the activities and priorities of the AusIMM are reviewed in order to clarify a frequently expressed opinion that it identifies with and supports industry at the expense of representing the interests of its individual members. By definition and by action this is certainly not the case and it is concluded that all activities whether seen to be industry or member orientated serve to benefit both. The AusIMM plays a most important role in integrating and promoting the interests of all sections of the mineral industry whether corporate or individual and the Presidential activities in education this year provide an excellent example of this.

Jan 1, 1997

By G P. W Suyantara, Y Tanaka, T Hirajima, Y Aoki, K Sasaki, H Miki

The effect of sodium sulfite (Na2SO3) on the flotation behaviour of bornite and tennantite is reported in this work. Flotation tests were performed using pure minerals of bornite and tennantite under various concentrations of sodium sulfite at pH 9. The flotation results indicated that sodium sulfite exhibited a depressing effect on the floatability of bornite in the presence of 0.1 mM PAX. However, tennantite remained floatable after the addition of sodium sulfite in the presence of 0.1 mM PAX. The flotation tests using mixed bornite and tennantite confirmed the flotation results of single minerals. Surface characterisation using X-ray photoelectron spectroscopy (XPS) was performed to explain the flotation results. A mechanism is proposed based on the XPS analysis results.

Aug 24, 2022

By M Laxman, A Kundu

After multiple tailings dam failures in recent times, the owner organisations have made increased efforts to step up the governance systems to industry best practise in the design, construction and operational management areas. The measures include but are not limited to, site investigation, rigorous peer review (both internal and external), certification through appropriately qualified personnel and improvement in operational management practises. While a lot of focus is on design and operational practices, the construction stage requires adaptation (both in terms of materials and approved design) and immediate decision making on site. Work undertaken in these areas is mostly irreversible and sometimes poses serious threat to the future TSF raise/ expansion planning and may lead to reduced life of the TSF and additional risk to the Owner.This technical paper will discuss some challenges and highlight the importance of appropriate processes to achieve a successful construction regime. The process will include a robust quality control/ quality assurance process, a team of designer-constructor-owner with suitable skills and technical understandings and robust documentation of the entire construction process from day 1 to the completion of construction.CITATION:Kundu, A and Laxman, M, 2018. Robust construction and quality assurance culture for tailings storage facilities – equally important as robust design and review practice, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 111–116 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

The activiltion of sphalerite with electrolytically generated copper ions from a copper electrode instead of the usual practice of the addition of copper sulphate was studied in the laboratory. A large surface area of copper was provided by lining three sides of a bench flotation cell with copper sheeting. The lining was connected to the positive terminal of a low voltage d.c. source, and the cell impeller to the negative terminal.Sphalerite was effectively activated by this arrangement and was subsequently floated using xanthate as the collector.Flotation results comparable to those obtained with 1 lb/ton CuS04.5H20 (0,255 lb/ton copper) were obtained using 0·1062 lb/ton of electrolytic copper and 0·488 kWh of electrical energy. The wastage of copper due to the formation of insoluble precipitates was found to be dependent on the length of time the current was passed. Maximum current was passed for the shortest time to minimize wastage.

Jan 1, 1973