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By M Taylor

The Project Specification and Technical Requirements documents associated with several recent large road tunnel projects within Australia have specified the application of AS/IEC 61508 – FunctionalSafety of Electrical/Electronic/Programmable Electronic Safety Related Systems at very high performance levels for the various control and fire life safety systems associated with such facilities.This paper seeks to explore the implications of referencing this standard within the road tunnel services context in terms of practicality, complexity and cost, whilst providing some examples of how a high safety integrity level (SIL) level can theoretically be achieved given current hardware availability.

Mar 8, 2011

By S Barrow, D Kent

Controlling the access of equipment, and people, has become more critical over the last few years for improving productivity and to meet safety responsibilities imposed by legislated obligations to have safety management systems. Hence Mine Site Technologies (MST) has spent the last three years completing the development of the tagging system to meet the mining industryÆs requirements, particularly streamlining access control. The basic tagging system tracks active Tags carried by personnel, or attached to vehicles and equipment, within underground zones. These Tags are detected (read) by Beacons placed strategically throughout the mine. As a Tag, or Tags, go past a Beacon they are read and the information transmitted back to the main database PC. This allows the current whereabouts of personnel and equipment to be known, as well as the history of their movements. The objectives of implementing the TRACKER Tagging System at Oaky No 1 Coal Mine were to: maintain a count of personnel inbye a particular point, and can alarm when a pre-set number is reached (eg the limit imposed by availability of SCSRÆs, etc); maintain a count of vehicles (and vehicle type) inbye a point, and can alarm if when a pre-set number is reached (eg when rated diesel units exceeds the limit for the ventilation present in that zone); manage the vehicle fleet, by keeping track of various vehicles underground better control and dispatch management of the equipment is achieved; keep track of equipment, knowing the location of equipment (such as forks, baskets, pumps, fans, etc) where last used or stored will minimise the risk of losing gear and assist in keeping inventory to a minimum; and locate personnel in emergency situations, by placing read Beacons throughout the mine the location of all personnel can be known in real time so that in the event of an emergency, their withdrawal can be monitored.

Jan 1, 2005

By M Franklin, C Puglisi, S Fitch

Implementation of a well planned and executed Management Operating System (MOS) can result in widespread improvements to operational performance but its success relies heavily on the investment by and engagement of the larger workforce with the project. Over the seven month period of the Telfer MOS project, significant improvements were achieved; a 20% increase in monthly hoisted tonnes from the open stope and sublevel cave operations and a 45% increase in square metres of ore extracted from the narrow vein operation. The Telfer MOS was undertaken with the intention that the project wasn’t solely about producing new tools, it hinged on the investment and behaviours of the personnel affected by these tools and alterations. To ensure that the project ran smoothly, the Byrnecut senior leadership team and their operators were heavily involved in the project’s development. In the initial stage, Telfer’s MOS project determined that the quality and accuracy of the information received in the form of radio calls to mine control and completed operator plods was questionable. This required an overhaul of the data collection and verification process in the form of altered operator plods, which was then cross referenced with the operator’s radio calls to mine control. Once the data collection and verification process was implemented, the Telfer team was then able to produce several tools with the aim of providing visibility to the data being captured and its implications. These tools allowed the mine foremen to determine whether equipment was being under-utilised and where they should focus their production efforts to meet monthly targets. Whilst the initial underground project is now complete, the implementation of MOS across the entire site is ongoing with significant operating improvements occurring.

Mar 15, 2021

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 E R. Ramanaidou

The presence of clays in channel iron deposits (CID) within the Pilbara region of Western Australia causes problems in the classification and subsequent processing of the iron ore. In particular, the presence of clay adversely affects the processing and ore metallurgical properties by increasing the amount of Si and Al. Iron ore companies are seeking new methods to quickly and objectively detect the type and amount of clay in these deposits. Traditional methods of clay quantification such as X-ray diffraction (XRD) and thermal analysis are time consuming and expensive. Reliance on bulk chemical techniques (eg X-ray fluorescence, (XRF)) to derive normative mineral abundances can give misleading results. For example, the replacement of Fe by Al in the structure of the iron oxide minerals, goethite and haematite, which dominate in CIDs, can be significant. Silicon can also occur in association with these Fe minerals. If not accounted for, chemical techniques may overestimate the normative abundance of clays. In comparison, reflectance spectroscopy in the visible-to-near infrared (VNIR) and short wave infrared (SWIR) wavelength range (eg 400 - 2500 nm) and Fourier transform infrared (FTIR) (6000 - 900 cm-1) analysis are non-destructive techniques that can provide rapid and objective mineralogical information. Both techniques are particularly suited to Al-, Fe- and Mg-OH bearing minerals such as clays. Kaolinite and, to a lesser extent, montmorillonite are the most common clay contaminants that occur in the Pilbara CIDs. Previous applications of VNIR-SWIR spectroscopy have demonstrated the potential of these methods in quantifying the clay mineralogy of CID ore. In this study, variations in the depth of diagnostic spectral adsorption features in the SWIR wavelength range of kaolinite and montmorillonite in standardised mixtures, with known proportions of clay, were well correlated to the abundance of kaolinite and montmorillonite, and to the clay alumina content (ie per cent Al2O3 û clay).

Jan 1, 2007

By G Lane, M Bueno

In a recent publication (Bueno and Lane, 2011) the authors presented the analysis of a consolidated dataset composed by 137 autogenous/semi-autogenous grinding (AG/SAG) mill pilot trials. By comparing the measured data against theoretical specific energy consumption, the analysis indicated which circuit configurations were more or less energy efficient. However, the analysis has also indicated that the energy efficiency of each of the types of circuits vary significantly.There are numerous factors that contribute to the variations of energy efficiency of AG/SAG mill-based circuits, such as feed size distribution, recycle ratios and ore characteristics. In view of this, the present work accesses these factors individually and discusses what may lead a particular circuit configuration to be more or less efficient in terms of energy and costs.CITATION:Bueno, M and Lane, G, 2012. Key drivers of energy and cost efficiency in autogenous/semi-autogenous grinding circuits, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 113-118 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By D Capstick, M B. Ebell

This paper describes the test work, process design, commissioning and operation of a processing system at the Ergo gold operation that improves the extraction efficiency from gold tailings material. The improvement in recovery is derived from the separation of the gold contained within the sulfides of the tailings material and a dedicated process stream to recover that gold.The sulfides are separated by means of a flotation circuit and that resulting concentrate is subjected to a regrind of below 20 ¦m to enable a greater liberation of the gold. The ultra-fine material is then subjected to a dedicated leach circuit to recover the now exposed gold particles.The case study is an example of the challenges of introducing new technology and methodologies to a well-established operation and thereby attaining improved efficiencies and tangible business benefits.CITATION:Ebell, M B and Capstick, D, 2013. Improving extraction efficiency from Witwatersrand gold tailings using flotation and ultra-fine grinding of concentrates, in Proceedings World Gold 2013 , pp 301-306 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By A Smith

Rock masses usually exhibit scale dependent mechanical properties primarily due to presence of discontinuities and their inhomogeneous nature. One of the essential preconditions for selection of appropriate strength and deformation parameters of a rock mass in relation to tunnel design is assessment of the scale of the joint network relative to the scale of excavation. In tunnel design practice, scale effects are estimated indirectly using small-scale unconfined compressive strength (UCS) tests and rock mass classification based empirical correlations. Large-scale UCS tests have the benefit of direct assessment of anisotropic and scale dependent properties of a rock mass.This paper presents results of a large-scale UCS test on a jointed siltstone. A 450 mm diameter sample with inclined bedding planes was cored and tested in uniaxial compression until failure with load and displacement measurements. The aim of the test is to determine strength and deformation parameters and correlate them with results of small-scale UCS tests of the same sample. The relationships between the small-scale and large-scale rock mass parameters were validated against published correlations from the literature.

Mar 8, 2011

By Wall L, Dobos S. K, Berry-Lyons W

The air we breathe and both plant and animal matter consist largely of nitrogen, oxygen carbon and hydrogen; each of these elements has two or more isotopes, The rocks, soils and waters on which we live and from which we extract minerals and other resources are comprised of elements such as oxygen, silicon, hydrogen, sulphur, iron and magnesium; each of which has two or more isotopes. Since isotopes of an element behave identically in chemical reactions, they cannot be separated or analysed by chemical means. The different isotopes of a particular element, however, vary in mass, reflecting the variation in the number of neutrons in their nuclei, so that physical processes based on the relative atomic masses of the isotopes are used to separate and analyse them (eg, mass spectrometry). Many biologic, atmospheric and geologic processes alter the ratios of the different isotop1ees of many elements. The isotope ratios D/H and O/ O, for example, exhibit significant variations in natural waters because of isotope fractionation during evaporation and condensation. Isotope analyses of both naturally-occurring and synthetic isotopes in the near-surface and biospheric environments can be used to understand natural processes and predict the results of man's interaction with his environment.

Jan 1, 1991

By R Bourcier, T Rafferty

Following an underground coal mine explosion, it is important that ventilation is quickly restored to ventilate the mine and affect a mine rescue. To achieve this, surface ventilation fans must be suitably protected from explosion damage, but still able to be quickly restored.A review of all Australian coal mine regulations was carried out, revealing that Australia has no prescriptive regulations that specify the design of explosion relief panels and the protection of ventilation fans in the event of an underground explosion.To better define the level of protection required, this paper reviews and extracts details from relevant major international regulations and standards on the subject.A suitable design methodology for the protection of ventilation fans is presented that could be applied in Australia, using a combination of explosion relief panels, appropriate isolation of the fan, and ventilation shaft/mine design.CITATION:Rafferty, T and Bourcier, R, 2013. The protection of surface ventilation fan installations from underground explosions, in Proceedings The Australian Mine Ventilation Conference , pp 169-173 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By M Gabbitus, B Young, T Lukins, M Slater

This paper details the implementation of a new type of grade control system at the Black Star open cut mine in Mount Isa, Queensland. It explores the site requirements for grade control, what as previously in place and what the site required moving forward. It also details some of the features of the system installed and why it was chosen over other grade control systems available. Black Star open cut mine has been in operation since late 2004, and was developed to extract the surface extents of the Ag-Pb-Zn mineralisation previously mined in the Isa Lead Mine. Black Star is currently mining seven distinct orebodies in and around active void hazard zones and hence, its grade control requirements are very detailed and complex. The implementation of a new system to manage the model update and block out processes was, therefore, of critical importance to the site and required a detailed understanding of the requirements of the entire mining team from drilling through to geology, survey and production. Having previously run the grade control process using site specific æblack boxÆ scripts and macros, Black Star needed to implement a more open, auditable and flexible system, which allowed the geologists to control the process and make strategic changes as the situation demanded. MineSightÆs Axis Grade Control, with its flexible, generic framework for managing the process, met these demands. Being an out of the box solution that requires minimal setup and training was also a key factor in the decision to use it.CITATION:Lukins, T, Slater, M, Gabbitus, M and Young, B, 2012. The introduction of axis at Black Star Open Cut, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 71-74 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

By H Lieberwirth, M Pfeifer, F Heinicke

HPGRs (high pressure grinding rolls) have been developed within the last decades for energy efficient processing of a wide variety of ores. Special interest has been raised by projects increasing the capacities of processing plants by installing HPGRs prior to ball mills. Bond ball mill tests have been used for decades as a base for ball mill dimensioning in mineral circuits. For final CAPEXOPEX considerations of the processing circuit, one key question is about the level of grinding energy split between HPGR and downstream grinding stages. This is especially interesting if the downstream process comprises multiple grinding stages combined with separation steps. The paper presents investigations on grinding energy consumption, size distribution and microfracturing of HPGR products, which affect the efficiency of the whole comminution and sorting process.

Aug 24, 2022

By J G. McLellan, B Miller

Copper and Gold mineralisation at the Ernest Henry deposit is bound by two controlling shears along the hanging wall and footwall margins. The shear zone geometries have been influenced by a large diorite intrusion, dated at ca. 1660 Ma, which lies to the north-east and south-west of the main orebody. The shear zones, which partitioned strain prior to the main mineralising event ca. 1514–1504 Ma, and in conjunction with adjacent regional structures, have been a critical factor in the deposit location and geometry. Conventional exploration techniques have been utilised proximal to the current deposit since the initial discovery in order to expand upon known resources, with limited success. However, new geomechanical modelling techniques have now been employed to target structurally controlled mineralised zones in three dimensions. The main aim of the geomechanical modelling was to simulate the effects of regional deformation events to highlight areas of anomalous strain, which indicate areas with a higher likelihood of fluid focusing and mineralisation potential. This project was focused on testing the latter stages of a D3 event (NE-SW compression) to examine preconditioning of the system, and a D4 event (SE-NW compression) which have ultimately been responsible for the current location of the mineralisation.CITATION:McLellan, J G and Miller, B, 2017. Geomechanical modelling of the Ernest Henry iron oxide copper gold deposit – identifying fluid pathways to predict potential mineralised zones, in Proceedings Tenth International Mining Geology Conference 2017, pp 75–82 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By E Acu±a, B Prosser, R Alvarez, K Wallace

This paper describes the ventilation analyses performed for the access tunnels at the New Level Mine project (NLMP) at CodelcoÆs El Teniente operation outside of Rancagua, Chile. This new mine is anticipated to reach a final production of between 137 and 180 kt/d. Production from the NLMP is scheduled to start in the year 2017. The main access tunnels (MAT) are approximately 9 km in length, with one for personnel and supply access and the second one for ore extraction through a conveyor system. These two tunnels are a critical component of the initial stage 1 development and will be constructed independently of the existing mine workings. The tunnels were originally designed to be constructed with two tunnel boring machines. However, later analyses changed the construction approach to a conventional drill and blast technique. Because the design included two mid-tunnel ramp-to-surface connections, conventional mining methods would allow for development of the tunnels with multiple working faces to achieve a more rapid schedule. This paper presents the initial baseline considered for the ventilation design and the optimisation methodology applied by Codelco to minimise the airflow and pressure requirements of the ventilation system. Modifications to the design resulted in the addition of strategic airways and raises that could provide a saving of approximately 1 MW, when compared to the original design.CITATION:Acu±a, E, Alvarez, R, Wallace, K and Prosser, B, 2013. Ventilation considerations for the new level mine project access tunnels, in Proceedings The Australian Mine Ventilation Conference , pp 203-206 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

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 M Norbert, C Bennett

The Legacy Way Tunnel was constructed from Toowong to Kelvin Grove in Brisbane, and is the first large-scale underground excavation in the Bunya Phyllite in Brisbane. The Legacy Way Tunnel is 4.3 km in length, comprising two mainline tunnels excavated by a tunnel boring machine (TBM) with 46 connecting passages excavated between the mainline tunnels for egress provision and services. The Legacy Way Tunnel passes through two geological formations, the Bunya Phyllite and the Neranleigh Fernvale Beds. The Bunya Phyllite is the dominant formation of the Legacy Way Tunnel, extending for three quarters of the tunnel prior to intersecting the Normanby Fault Zone (NFZ) and the Neranleigh Fernvale Beds. The NFZ forms the contact between the two formations as part of the Brisbane Metamorphics, which underlies the majority of Brisbane City. The development of the geological model and the understanding of the ground’s reaction to tunnelling was an iterative process. The tender phase investigation data has been supplemented with additional design phase investigation boreholes, geophysics and walk overs. Aerial photograph interpretation coupled with borehole data allowed the development of the domains along the length of the tunnel. Early excavations for the spoil conveyor tunnel and borehole data from subsurface instrumentation installation provided the first construction phase data followed by the commencement of tunnel boring machine (TBM) excavation. Routine cutterhead inspections coupled with ongoing reviews of the predicted geology resulted in clear response triggers to selection of segment types while detailed inspections in passage locations provide the initial classifications for segment removals.CITATION:Bennett, C and Norbert, M, 2014. Tunnelling within the Bunya Phyllite of Legacy Way, Brisbane, Queensland, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 131–140 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By M Yadav, K Clode, S Daykin

The mining industry faces numerous challenges related to sustainability and circular economy principles, necessitating strategic approaches to innovation and resource management. As demands for mineral resources continue to rise, mining companies are under increasing pressure to address environmental impacts, minimise waste generation, and optimise resource utilisation. These challenges underscore the importance of Research and Development (R&D) roadmaps as strategic tools for guiding innovation and sustainability efforts within the sector (Jochen Berbner, 2022). A design-led methodology offers a structured approach to R&D roadmap development, emphasising stakeholder engagement, collaboration, and alignment with industry objectives. By leveraging design principles, mining companies can ensure that their R&D initiatives are responsive to evolving challenges and opportunities, fostering a culture of innovation and continuous improvement. Against this backdrop, the project aims to address the pressing challenges associated with sustainability and circular economy in the mining industry. Through the development of R&D roadmaps and the application of a design-led methodology, the project seeks to identify innovative solutions for enhancing resource efficiency, minimising environmental impacts, and promoting sustainable practices within mining operations. This paper highlights the collaborative efforts among Isle, the mining industry, and water utilities, which have yielded tangible benefits. The study demonstrates how the outcomes from the roadmaps outlined below effectively align research with strategic objectives, fostering innovation to address pressing challenges.

Sep 1, 2024

By J A. Rowland

When executing a ventilation change the mine ventilation circuit is in a state of flux throughout the entire change period with discrete mine areas both under ventilated and/or over ventilated during the change process. Whilst routine risk reduction strategies such as removing electrical power and people from the mine are commonly deployed it is wise to complete the change in the shortest practical time frame. This not only minimises the chance of unacceptable concentrations of contaminants accumulating around the mine but reduces the impedance on production activities which are routinely suspended during these change periods. This paper firstly highlights the importance of the maintenance of an accurate ventilation model and discusses issues which should be considered to assist to maintain in it a suitable state of health. Further it provides some tips on how to monitor that your model is in an acceptable state of tune so that it can be confidently deployed in the change process. Finally, it details the sequential process how a finely tuned and accurate ventilation model can be utilised to carry out major ventilation changes according to appliance pressure adjustments only and without the need to constantly measure and check resultant branch flows throughout the whole change process. Also discussed are some simple practical tips which will help ensure that the ventilation change process will go according to the devised plan on the day and in the most appropriate order including checking the efficiency and accuracy of the change, after it is completed.

Oct 12, 2022

By A Bax, G Wardell-Johnson, W P. Staunton, J McGrath, J J. Eksteen

Since 2001, the AMIRA P420 gold processing technology project series has been studying the recovery of gold using gravity devices, with particular emphasis on the centrifugal units, Knelson and Falcon concentrators. The work has entailed the surveying of operating gravity circuits in Australia, Africa and North and South America.This paper reviews some of the results and lessons of these studies, including common circuit operating and design factors, which limit gravity recovery; pointers towards effective modelling of gravity circuits; and the contribution of gravity to overall gold recovery.CITATION:Wardell-Johnson, G, Bax, A, Staunton, W P, McGrath, J and Eksteen, J J, 2013. A decade of gravity gold recovery, in Proceedings World Gold 2013 , pp 225-232 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By P Holtham, R Dunne, D Stoll

Flash flotation is a process designed to remove coarse, liberated, fast floating minerals from hydrocyclone underflow. Irrespective of liberation, coarse particles would normally remain in a grinding circuit until they are reground fine enough to report to the hydrocyclone overflow. Additionally, minerals of high density also report to hydrocyclone underflow despite being fine in size and/or liberated because hydrocyclones separate on the characteristics of both particle size and density. Dense particles continually reporting to the hydrocyclone underflow can lead to over-grinding and the production of ultra fine particles. These particles exhibit slow flotation kinetics and thus are difficult to float in conventional flotation circuits. Therefore, removing coarse, liberated particles from the hydrocylcone underflow by flash flotation has the potential to improve recovery and can improve dewatering unit operations and reduce grinding costs.The impact on the overall performance of the flotation circuit by removing coarse, fast floating minerals prior to conventional flotation is not well understood. Ultimately, predicting the overall recovery improvement provides the justification for the installation of a flash flotation cell within the milling circuit. This paper will describe attempts to estimate flash flotation recovery improvements to the overall circuit using kinetic data from simplified batch cell flotation tests combined with limn-based modelling techniques.CITATION:Stoll, D, Dunne, R and Holtham, P, 2012. Modelling the impact of flash flotation from batch cell flotation tests using limn, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 179-184 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012