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By D David

Amongst those whose task it is to design tumbling mills and other comminution machines there is an almost religious divide between devotees of the Bond method and devotees of other methods developed in more recent times. For a decade or so the issue was between the Bond power-based methods and the JKMRC (JK) simulation based approach. The newest method to challenge the status quo is power-based and was developed by Steve Morrell. As the title suggests, this paper will take some liberty at concluding that Fred Bond and Steve Morrell may be separated by history, but not by their approaches to their individual contributions to the science of comminution. Another driver for the paper is that although it is good to have diversity of thought, the existing divisions are problematic for those of us signing public disclosure documents. If alternative design methods produce materially different outcomes for the mill duty, then at least one of them is wrong or being used incorrectly. At some point the unsustainable argument may need to be put in a court of law that we metallurgists have two or more materially different design methods, each of which is correct! Therefore, perhaps a resolution is needed before this occurs?The works of both Fred Bond and Steve Morrell are each directly related to their contemporary grinding mill design and operational environments. Both their approaches are empirical, borne of observing and measuring real world situations. Both worked with theories that preceded them, gathered their own data and then each saw shortfalls in the status quo.Fred Bond was an escapee from revolution, a victim of The Great Depression, and had several near death experiences during his early site-based career. Perhaps he was fortuitously rescued from himself when asked by Allis Chalmers (A-C) to set up its rock testing laboratory in Milwaukie in 1930. Fred’s testing led him to conclude that neither the Kick nor the Von Rittinger theories explained his measurements. His writings on the failings of these old theories caused a divide between devotees of the old and new methods at that time. After many years, and much thought and plotting of data (the old way!), he came up with his now-famous equations (and his Third Theory) which have stood the test of time, certainly in the world of Bond-era machines.Coming from England via several African diamond mines, Steve Morrell immersed himself into the comminution world of the JK in Brisbane about a decade after Fred passed on. The JK had developed its semi-autogenous grinding (SAG) simulation framework using its own pendulum breakage tester, itself a derivative of the twin pendulum impact device invented by Bond decades earlier. At the JK Steve developed his authoritative Tumbling Mill Power equations and was involved in real world analysis of comminution problems on the global stage. Steve’s JK experience coincided with the demise of the rod mill, the rise of autogenous grinding (AG) and SAG milling and a rapid expansion in concentrator capacity.Morrell left the JK to pursue his own interests, which included ongoing consulting work, now demanded by the comminution world. He then turned to investigating a growing list of discrepancies between the opinions of designers and theoreticians, and the factual outcomes. The Morrell Method of design arose from this re-examination of ore testing, real world operating data and these glaring and expensive discrepancies between design and outcome. The elements necessary for a relook at the world of rock breakage were in place!CITATION:David, D, 2017. Steve and Fred would have been mates – a comminution design evolution story, in Proceedings MetPlant 2017, pp 2–11 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By M B. Lovitt

At present there exist few engineering calculations and principles to determine exclusion zones for personnel in the vicinity of underground explosive storage areas. This paper is written to encourage discussion and proposes a method to determine the impact of a blast wave through scientific principles. Then, criteria to determine an ‘exclusion zone’ need to be identified.There has been much work on identifying the pressure rise and the energy of explosive detonations underground but little to develop standards in criteria that can be used to identify exclusion zones for useful design of underground infrastructure. The author presents the newest ways of calculating the pressure rise and energy (impulse) of detonations and puts forward some criteria to be used in the identification of personnel exclusion zones to spark peer review and discussion of these criteria towards developing standards for engineering design.Smith and Sapko (2005) used Sach’s scaling laws to develop a relationship for both pressure rise and impulse, which incorporated factors for intersections. Intersections will have a large bearing on the peak pressure and the energy of the blast wave and needs to be incorporated. Silvestrini, Genova and Leon Trujillo (2009) developed the scaling laws with an energy concentration factor to predict blast propagation in partially confined geometries and together the author has proposed equations for determining the peak side pressure and the impulse in a tunnel. Given the weight and type of the explosive, the average cross-section of the tunnel complex and the number and type of intersections encountered, the pressure and impulse can be calculated.The military has carried out many investigations as to the influence of blast pressure and impulse on the human body. Lung damage, ear damage and velocity knock down are three of the criteria standards that are presented as possible methods of determining exclusion zones around an underground explosives magazine. The author suggests that the velocity curves presented by Bowen, Fletcher and Richmond (1968) could be an acceptable method of determining an exclusion zone as it incorporates the side pressure and the energy of a blast wave to determine the ability of the wave to knock down personnel.CITATION:Lovitt, M B, 2014. Exclusion zone calculation for underground explosives storage, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 319–326 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

By A L. Randriamanjatosoa, G Small, C Greet

In flotation simulation models, the effects of pulp chemistry other than pH are often ignored and reduced to particles hydrophobicity or contact angle, neither of which can be measured readily in real time in an operating plant. The flotation response of a given sulphide mineral is known to be influenced and can be improved by changing the chemical characteristics of the pulp during grinding and flotation. The on-line measurement of pulp pH, potential, dissolved oxygen, temperature and oxygen demand of a process stream was completed with the PCM® (Pulp Chemistry Monitor) developed by Magotteaux in this study. The data generated together with relevant plant operating parameters were used to construct an empirical model and simulate the metallurgical performance of the ore. The same approach was also applied to laboratory flotation tests data using various grinding media types. The flotation models better fit the actual data when the chemistry of the pulp is taken into account.CITATION:Randriamanjatosoa, A L, Greet, C and Small, G, 2018. Effects of pulp chemistry on plant and laboratory flotation modelling, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 423–432 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By G Phillips

The Merlin project is situated 130 km south of Cloncurry in North West Queensland, Australia. It is located within the Pre-Cambrian Mt Isa Inlier and is grouped within the Eastern Fold Belt. The host rocks are metasedimentary rocks of the Proterozoic Kuridala and Staveley Formations adjacent to the Mount Dore Granite.Merlin zone represents part of the Mount Dore polymetallic deposit containing copper, zinc, silver, gold, lead, cobalt and most recently has been found to host molybdenum mineralisation. This is intimately associated with economic grades of rhenium, a naturally occurring metal that is an important component of high temperature aircraft engines. The host rock sequence is a 200 m thick zone of metasediments sandwiched between competent granite in the hanging wall and brittle quartzite in the foot wall. A distinct shear marks the contact between the granite and metasediments. The host rocks are comprised of three main rock types: black shale, phyllite and altered banded calc-silicate.Mineralisation dips to the east at approximately 45° in a package of fine grained pelites and banded calc-silicates. The top 150 m of the sequence is typified by black shale and phyllite. The lower 50 m is typified by pink banded calc-silicate. The main molybdenite zone is located at and parallel to the pelite-calc-silicate contact. Down dip, the zone splits into two or three veins hosted by the calc-silicate rock suite and haloed by thin, steep dipping, stylolitic molybdenite veinlets.The deposit was discovered in 2008 by routine infill reverse circulation sampling conducted for the Mount Dore copper deposit. One hole penetrated below the main target Cu horizon and intersected visible molybdenite. During 2009 and 2010 a 50 × 50 m diamond drill pattern delineated a total mineral resource of 6.7 Mt @ 1.3 per cent Mo, 23g/t Re, 0.3 per cent Cu (mostly Indicated Mineral Resource with minor Inferred Mineral Resource). The resource has been estimated using ordinary kriging within grade domains. Access to the deposit has commenced via a decline and production through the nearby Osborne flotation concentrator (70 km south) is expected in 2012. All facilities and resources are fully owned and operated by Ivanhoe Australia Limited, a public listed company on the Australian and Toronto stock exchanges.

Aug 22, 2011

By C Dowding, C Aimone-Martin, P Abeel

This paper presents measurement and analysis of the dynamic response of a five-storey building to very high frequency excitation (>100 Hz) from blasting vibrations originating from a contiguous excavation of rock. Velocity response measurements in the rock and on the structure were employed to calculate the time-correlated dynamic displacement response of the building to blasting. Time-correlated structure response measurements are needed to advance the understanding of the response of urban structures to high-frequency excitation. Current regulations and understanding are based upon measurements of the response of one- to two-storey residential structures by 10 to 40 Hz excitation. The extension of these observations to taller structures when excited by high-frequency excitation needs to be investigated further.Measurements show that the amplification patterns at the ground level and top of the structure match or are lower than that observed by the US Bureau of Mines (Siskind et al, 1980) for the shorter residential structures. They decrease with increasing peak particle velocity. From the measurements, the global transverse shear strains found by differentiating ground floor and top displacements were calculated to be 12 µstrains. Time-correlated bottom and top of structure displacements show that building response may be more reflective of wave propagation up the structure than whole-structure inter-storey drift.In addition, a 3D model was used to compare computed displacements and strains to measured results. Modelled responses varied considerably, both in magnitude and location of the maximum strain. No conclusion can be made regarding the best 3D model to employ to simulate building response. More data such as motions measured at many points in the structure are needed. Maximum inter-storey transverse shear strains calculated with the model were found through the acceleration excitation and were less than 12 µstrains for 37 mm/s rock motion excitation. The inter-storey transverse shear strains calculated with rock displacement input were less than that found with the acceleration excitation.CITATION:Dowding, C, Aimone-Martin, C and Abeel, P, 2015. Measured and modelled response of a multistory, urban structure to high-frequency blasting excitation, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 211–220 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By V Chamberlain, M Appeah Owusu, M Aniawu-Asumakah, A Anyimadu, R Peattie

This is an integrated geology and plant improvement study arising from the heterogeneity seen in mineralogy and gold association at the Obuasi goldmine in Ghana. This heterogeneity comes from the two ore types mined, the one being a sulphide ore, mainly composed of gold-bearing arsenopyrites. This gold is refractory and exhibits a strong relationship between gold and As. The other is quartz veins, that are high grade and free milling. The installed circuit consists of comminution – Gravity -Flotation – BIOX – Leaching and Adsorption processes. The opportunity tested involved improved mass pull - related flotation recovery of Au in the Sulphide stream; while balancing the need for a minimum Sulphide grade for the Bio-oxidation process, occasioned by the removal of 25 to 30 % of the (quartz) stream through preconcentration by Ore sorting. The current circuit is then utilized for the sulphide route, while a smaller grind-gravity circuit is utilised for the quartz stream in a relatively inexpensive way, followed by a common leaching and adsorption circuit. Added advantages of the strategy includes faster recovery of gold from the quartz stream, with less consumption of reagents from saving on flotation and BIOX reagents for this stream. Screening and Ore sorting was successfully tested with laser technology, achieving over 98% separation of quarts (containing up to 40% of the gold). The plant schedule of Ore, the suggested circuit design for the Ore sorting, the results obtained from the different flotation regimes, as well as consequent financial modelling have been presented and discussed in this paper. This illustrates the opportunity that arises out of a detailed analysis of material versus installed circuits, even if the gains in pre-concentration do not necessarily involve rejection of gangue material. An added opportunity for future investigation, briefly discussed but not tested in this paper, would be to maintain current mass pulls but with increase in throughput (by the space created by the sorted material). This will of course require the mining ability. It could also add LOM value by altering the cut-off grade.

Nov 10, 2020

By I D. Gregson, A Gandhe, A S. Garcia, K M. MacAndrew

"Falls of ground still cause around one-third of all underground mining fatalities. The recent introduction of mechanised room and pillar working into Indian coalmines is an example of the application of new design by measurement and safety monitoring strategies, which can be used to reduce falls of ground risks in mines.Rock Mechanics Technology, now part of Golder Associates UK Ltd (Golder), is providing rock bolt support and pillar design services to the mines using a design by measurement approach. This involves in situ monitoring to confirm support and pillar designs and pillar extraction sequences.Site examples are given of the support designs determined and the monitoring programs undertaken for both design and safety.Routine safety monitoring of roof movement using telltales is also described. A new auto warning telltale has been developed specifically to warn of imminent caving as pillars are extracted.The approach used by Golder has played a major role in ensuring the success of these projects. As a consequence, mechanised room and pillar working is now firmly established in India, and wider application is planned to help meet future demand for coal.The experience confirms that the design by measurement method for this application has important advantages over conventional design approaches using analytical or empirical methods. Firstly, it measures the design performance or outcome rather than trying to calculate or predict it. Secondly, it provides the opportunity for the design to be adjusted to obtain the optimum outcome. Thirdly, it can do this at a local level, so that the support design can be matched to changing conditions to give the most cost-effective design. Finally, it incorporates long-term monitoring of support performance, again at a local level, so that subsequent change can be identified to enable corrective measures to be implemented in a timely manner and to ensure that ground control safety is maintained.CITATION:MacAndrew, K M, Garcia, A S, Gregson, I D and Gandhe, A, 2014. Application of design by measurement for support and pillar design in mechanised room and pillar coal mining in India, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference, pp 65–76 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 5, 2014

By K Afewu, R Dunne, W P. Staunton

The treatment of preg-robbing gold ores has always been a technical challenge in the gold industry. Early solutions included removal of preg-robbing carbonaceous material by flotation, the addition of kerosene to æblindÆ/passivate the surface of the preg-robbing component, and the most effective of all options, roasting the ore. Unfortunately gold ores have become more complex and roasting has environmental challenges, so other methods of treatment have had to be found. This paper will review methods of characterising preg-robbing gold ores, method of treatment and cite examples of actual application in the industry.CITATION:Dunne, R, Staunton, W P and Afewu, K, 2013. A historical review of the treatment of preg-robbing gold ores - what has worked and changed, in Proceedings World Gold 2013 , pp 99-110 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

In the UK during the 1990s the energy companies had developed a policy of æDash for GasÆ, building large natural gas power stations to produce more than 30 per cent of the UKÆs electricity demand. The price of imported thermal coal was dropping and the electricity generators were putting pressure on the UK coal producers to produce coal at a reduced cost. Imported coal from Columbia, South Africa, America and Australasia had increased their market share in thermal coal sales to over 50 per cent of a 55 Mtpa market. The pressure on the UK coal industry to reduce costs and improve productivity levels from an ever decreasing resource was high. Companies were benchmarking their operations on the imported coal producers and had to realign their organisations, productivity levels and costs to world best practice, not just technically, but in world class organisational management techniques.

Jan 1, 2005

By K G. Harding, E L. Haggard, C M. Sheridan

Mining is a water intensive sector, contributing to declining water resource quality around the world. Improvements to current mine water management practices can help reduce the amount of water utilised by the mining sector and the impact on water resources. Creating a water account can help companies understand water use in their operations and identify areas where water reduction is possible. Water accounting methods include the Water Footprint Network method and the WaterMiner tool.The Water Footprint Network method is used to determine the amount of direct and indirect water used by an organisation either in a process or to manufacture a product. The total water footprint is divided into the blue, green and grey water footprints. Blue water is the amount of water abstracted from surface and ground water resources. Green water is the amount of rain water utilised. Grey water is the amount of freshwater required to assimilate the waste stream to the natural resource and still conform to ambient water quality standards.The WaterMiner tool is a program available via the internet, which can be used to model water use of mineral processing sites. The program reports the amount of raw, worked and treated water used by the process and recommends flows that can be added to reduce the amount of fresh water required by the process.To gain information on mine water management practices in South Africa, a water account for a platinum mine was developed using the Water Footprint Network method and WaterMiner tool. Based on the results, suggestions to reduce the amount of fresh water utilised are made.CITATION:Haggard, E L, Sheridan, C M and Harding, K G, 2013. Water footprint for a South African platinum mine, in Proceedings Water in Mining 2013 , pp 15-20 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 26, 2013

Access to the Rosebery Orebody, which dips into the western slopes of Mount Black at 45¦, has been achieved in sequence by the following means: - A series of adits down to 8 level - An inclined shaft (No. 1 Shaft) sunk internally from 8 level to 14 level - A vertical circular concrete lined shaft (No. 2 Shaft) sunk internally from 4 level to 19 level. Although the orebody has been fairly well defined to 19 level, deeper ore occurrences have been outlined by a series of drill holes decreasing in frequency with depth to 26 level. No. 2 Shaft (sink) was stopped some 10 m below 19 level in order to make an early start on doubled production at West Coast Mines, with the intention of subsequently extending the shaft or of driving a decline from the lowest operating horizon for deeper access. The decline approach was adopted some six years after production commenced from No. 2 Shaft. The reasons for that decision are outlined, together with an account of the constraints and design requirements imposed by commencing by a vertical shaft in the hanging wall of the orebody.

Jan 1, 1982

The Channel Tunnel is an outstanding example of an undersea tunnel and its design illustrates most of the unique features of this type of tunnel. The marine site investigation was partic- ularly vulnerable to adverse weather conditions. To minimise this interference the time the drilling vessel was required to remain on station was kept to a minimum by expediting the drilling and the insitu tests as far as was practicable. To avoid additional unforeseen costs the contract documents were framed to take particular account of marine practice. The limited access at the coast line meant that for economy, maximum tunnel advance rates had to be attained. Ground excavation, handling and disposal methods and the provision of the lining were optimised and equipment specified in detail to ensure that no one com- ponent was delayed by a lack of capacity or mechanical failure in any other.

Jan 1, 1976

By R Daiyan, G Burge, M Haider Ali Khan

Australia’s mineral and metal exports have a substantial carbon footprint, twice that of its domestic emissions, mainly due to fossil-fuel-dependent downstream processes like processing into secondary metals and their transport. The country’s vast renewable energy and low-carbon hydrogen potential offer a promising alternative to mitigate this impact. These resources can be leveraged to displace fossil fuel use and become embedded into the metals value chain. Ultimately, it will yield ‘Green Metals’ that can be scaled to reduce the environmental footprint and provide an avenue for Australia’s vast green resources to be embedded (incorporated during production and supply) in green metals that can be exported. One potential green metal is copper, which is in great demand and likely to drive global decarbonisation through renewable electrification due to its role as an energy conductor. Given that Australia is a large producer and exporter of copper, this paper provides a techno-economic model of the copper value and applies it to Queensland (a hub of Australia’s copper production) as a case study. The results show that under incumbent hydrogen (A$8/kg) and renewable energy costs, the cost of green copper would be A$9704/t (~10 per cent higher than current copper costs). Further analysis revealed that the cost of hydrogen is a major cost driver; therefore, if the cost of hydrogen can be reduced to A$2/kg (a 2030 target of the Australian government), the cost of green copper would become competitive. Furthermore, if a carbon pricing regime ($54–79/kgCO2) is introduced, green copper would become competitive at a hydrogen cost of A$3/kg. Altogether, these findings provide insights for a future green copper export opportunity in Australia. Additionally, as the next step, the model can be extended to include other metals and released as an open-source resource for assessing global green metal opportunities.

Sep 1, 2024

New technology is a significant factor in the present upsurge in world, and Australian, gold extraction and production. The main technologies in current use for gold production are described, referring to overseas developments. Areas where existing techniques have shortcomings or new methods are needed are pinpointed and discussed. Much research work on gold metallurgy is under way round the world, and many new developments have potential. Many of the current research activities round the world are covering unusual and striking areas, with surprising results starting to come through. Some of the "blue sky" techniques reportedly under investigation are identified, together with consideration of when changes in technology are of value. The consequences of new technology for personnel involved in gold plant operations will be raised, including the new education now required.

Jan 1, 1986

By A Atkins

Six recent case studies were selected based on the eight main causes of mine disasters (Table 1; Quinlan, 2014) and where credible information sources, such as Royal Commission Reports, Coronial Investigations and textbooks, were available. The six case studies are listed below. Details are available via this link or the conference PowerPoint accompanying this paper. 1. Beaconsfield, Tasmania – 2006 Fall of Ground/Seismic Event (Chandler, 2009; Melick, 2007; Wright, 2012). 2. Bingham Canyon, USA – 2013 Manefay Slide (Ross, 2017). 3. Bronzewing, WA – 2000 Hydraulic Fill Inrush (Hope, 2002). 4. Brumadinho and Samarco, Brazil – 2015 and 2019 Tailings Storage Facility (TSF) failures (Bowker, 2019; Darlington et al, 2019; Demajorovic, Lopes and Santiago, 2019; Morgenstern, 2016). 5. Northparkes, NSW – 1999 Cave Air-blast (Bailey, 2003; Hebblewhite, 2003). 6. Pike River, NZ – 2010 Methane Gas Explosion (Macfie, 2013; Panckhurst, Bell and Henry, 2012.

May 5, 2022

By S Zheng, Y Zhang, Z Wen, S Ma

Red mud (RM) is a solid waste product generated during alumina refinery process, and is usually stored in SFs (SFs) because it canÆt be disposed of easily. In this paper, environment degradation caused by RM-SFs was systematically assessed by the method of single factor pollution index based on the analysis data of water, soil and atmosphere sampled around one newly-built and one decommissioned RM-SFs, which are managed by an alumina production company in China. The results revealed that the ambient environment around RM-SFs is seriously polluted by alkali and mercury (Hg). The pH value of RM leachate, surrounding surface water and groundwater are all higher than the limit of water quality standards in China. And as a possible result of overflowing of high alkaline leachate, soil pH value for the decommissioned SF decreases with increasing distance between the sample collection points and the closest side of RM storage facility (RM-SF). Total Hg concentrations in RM leachate, surrounding surface water and groundwater all exceed Grade III limits of ChinaÆs Environment Quality Standards for Surface Water and Groundwater. However, the air quality was little affected as the daily average of TSP in the air is below grade II values of Chinese Ambient Air Quality Standard.CITATION :Wen, Z, Ma, S, Zheng, S and Zhang, Y, 2012. Assessment of environmental quality impacts caused by red mud storage facilities in China, in Proceedings Life-of-Mine 2012, pp 51-58 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By H He, S Tillotson, S Gibbons, J Shaw

"Water evaluation and management during mining exploration and operational activities is crucial to minimise direct and indirect operational costs and also in delivering mining companies the less tangible, but equally critical æsocial license to operateÆ.Mining is often carried out in remote areas, where the mine will be the most significant and visible user and potential contaminator of water resources. However, wherever it is located, a mineÆs use of water must be managed in the context of two key aspects: the natural parameters of the resource; its abundance, its temporal variability and its chemical and physical qualities other users of the resource; other industry, potable water supplies and ecological requirements of local habitats.It is vital, therefore, that this commodity be assessed to an appropriate degree to help establish the viability and sustainability of the mining project and identify those other stakeholders who may be affected by the mining companyÆs activities.This paper outlines the background to catchment-scale model and presents a cost-effective method for establishing a robust water baseline and creating a water management tool to be used throughout whole mine life cycle. Numerical surface and groundwater modelling has long been established as a tool for reactive management, following collation of yearsÆ worth of data. Now, using freely available remote sensing data and desk study information, analytical modelling techniques can be used cost effectively to provide mining companies with a tool for assessing and managing their water consumption requirements at the outset of a new project venture.The paper includes a selection of case studies to show how the use of analytical modelling can be used as an evaluation and management tool to help not only assess general watershed parameters and water availability but also how it can be used as a tool to provide decision makers with the information to complete æwhat if?Æ scenario assessments. The case studies illustrate how a combined hydrological and hydrogeological model may enable identification of sensitive receptors, water competition issues and contaminant migration pathways to help manage the risks associated with water consumption and its potential contamination from exploration and operational activities.CITATION:Gibbons, S, Shaw, J, Tillotson, S and He, H, 2013. Catchment-scale water modelling and its role in risk management during mining exploration, in Proceedings Water in Mining 2013, pp 175-188 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 26, 2013

By J Johansson

The aim of this paper is to discuss how to form work and organisations in the mines of the future. The Kiruna underground iron ore mine in the far north of Sweden is used as an example on how technical development affects organisational issues like skills, work identity and gender. Over a period of 50 years one can see a transformation of work from manual underground work to automation and remote control from surface level. What characterised the old underground workface was the close relation between man and the hard rock and with arduous physical work under dangerous conditions. Today, the face miners are located on the seventh level of an office building close to the mine. There is also an emerging, and in many aspects already evident, knowledge transformation û from the old and obsolete physical and tacit knowledge and skills (for example the ability to æread the rockÆ) to something new, which can be described as abstract æhigh-techÆ knowledge and skills. The modern technology has created a new type of work û new in terms of competencies and knowledge as well as workload and organisation. At the same time the mining company are recruiting more women and promoting the former pure male work as attractive workplaces for both women and men. All this has effects on how individuals and company create and recreate skills, identity and gender. To some extent the technological development predestines these changes, but there are some choices to be done when forming good work and organisations for the mines of the future. The traditional mining workplace culture and behaviours and the old type of masculinity, the æmachoÆ style, will be challenged by the new æhigh-techÆ work and new competency demands. The changes risk meeting restoring responses, which can have negative impact on the performance of the organisation, for example making it inflexible and perhaps ælaggingÆ behind the technological development. These questions need to be handled when planning future mining.

Jan 1, 2008

By A Dennis, T Hunter, R Coleman

For metallurgical plant design, it is necessary to progress through successive phases of test work, piloting and process development before involving all the other engineering disciplines and “freezing” the process design criteria and flow sheet. This process usually relies upon the experience, skills and personal preferences of various technology providers, study and engineering entities, test work and metallurgical laboratories and, most importantly, the owner’s team and its operators. Current industry trends include lower grades, more complex orebodies, geometallurgy in defining orebody variation and design envelopes, more common “hybrid” plant processes and the market demands for more reliable, timely and predictable early plant performance.This paper will discuss interaction of these trends and provide guidelines for the level of detail and technical complexity required for a number of different “typical” examples. The paper will pay particular attention to the study definition level translated into the required detail and certainty needed by the overall process “owner” and original equipment manufacturer (OEM) equipment suppliers to ensure the best real plant performance. Some recent case studies will be discussed. In many projects, at a late stage of project definition, it has become common practice to undertake a “value engineering” phase. Although it could be argued that this should be undertaken earlier, it is largely driven by an overall need to reduce capex and “optimise” the perceived “fat” built into the project during the detailed design process. This value engineering can be very counterproductive to project timing and operational performance and warrants discussion.The paper is intended to promote discussion on a topic of wide interest. The authors’ diverse backgrounds and experiences are integral to the views in this paper.CITATION:Dennis, A, Coleman, R and Hunter, T, 2017. Critical process design considerations from test work to operations, in Proceedings MetPlant 2017, pp 12–30 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By J Westh, S Rashleigh, L Gallagher

Mining companies are moving towards automated haul trucks and other equipment. One reason for this is that if automated trucks can operate in a standard pattern over and over again without variation, then human error is reduced, if not eliminated.The challenge for mining production leaders/managers is to ensure operators follow standard operating procedures for load and dump operations, with each operator doing the same thing, every time. However, operators are only human and inconsistent performance is rife at every mine site. The finger may be pointed at the operators for not doing as instructed. The clarity and variability of trainer instructions may be considered causal to the problem. Herein lies the problem. Almost all operators believe they are following the procedure very closely; moreover, they all demonstrate a strong desire to conform to instruction.Using video analysis and feedback, each operator can be shown where and by how much they differ from the benchmark set by their company. Operators, often for the first time, can see definitively what they are doing, compared to industry best practice.The technology utilised by real-time video (RTV) crews measures time, distance and angles. It can overlay the video of the operator at the load site, with video of the perfect pass. Operators are amazed when they see how near to, or how far they are from best practice.The footage and data gathered by RTV assists operators in understanding exactly what adjustments are required to increase proficiency. It also assists load and dump superintendents to identify where in the process they are losing time. When translated to overburden removal or mineral/resource extraction, the result is large production economies without the need for large capital investment in new automated technology.CITATION:Westh, J, Gallagher, L and Rashleigh, S, 2012. Improving safety and mine productivity using real-time video technology, in Proceedings International Mine Management 2012, pp 173-188 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012