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A very wide range of technologies are utilised in the mining and processing of ores and a great deal of effort is expended in the development of ænew technologiesÆ to improve mining performance and economics. Traditionally, technology and people have been treated as separate aspects of an operation, when in fact they are inextricably linked. The successful implementation of new technologies is entirely dependent upon the actions, enthusiasm and skills of people, both as individuals and working in groups. This paper discusses the role of technology in mining and how new technologies are implemented by the industry. The paper argues that existing technologies have not been fully or adequately utilised and that effort should be re-focussed on the implementation of technologies that have been taken for granted for many years. The need for greater emphasis to be placed on the management of the human-technology interface is discussed.

Jan 1, 1998

By P Velletri, N Gaylard

The management of wear surfaces in mining operations has remained largely unchanged since the inception of mining. Sacrificial wear liners are installed on the inside of chutes, hoppers and other equipment used to transfer bulk ore to protect the asset from abrasive wear caused by the flow of material. These liners are generally replaced at fixed intervals which may be determined based on historical wear rates or may be driven by other maintenance requirements for that asset. This approach does not always yield satisfactory results, especially for critical assets where the impact of downtime on production can be substantial. For such assets, a condition-based maintenance strategy has the potential to significantly increase productivity and reduce the total cost of ownership associated with the asset. However, for such a strategy to be successful, timely information on the actual condition (remaining thickness) of the wear liners is essential. This paper describes the development and implementation of a wear monitoring system that can be used to remotely and continuously report on remaining liner material thickness in real time. It details some of the challenges that were overcome when developing the system, including the design of a patented thickness measuring system that can be used in a variety of liner materials and is tolerant to the presence of ore on the wear surface. The paper also explains how a cloud-based approach enables data from the wear sensors to be integrated into external systems such as a data historian, which has been demonstrated through a collaborative project with one of the largest iron ore producers in the Pilbara. This ability to combine real time liner thickness information with other data sources, such as throughput, provides the foundation for the transition to a condition-based maintenance strategy.

Nov 8, 2021

The resource sector is conservative industry and people are resistant to change. The methods and procedures used to implement changes in process plants ultimately determine the success of such changes. The financial managers have a large say in where money is spent and the technical personnel must justify the cost and benefits for any expenditure. There are also others who believe it canÆt be done û æwe tried thatÆ. Implementing change needs a æChampionÆ who can assess the risks, plan, define the objectives and scope, set the goals, determine the key performance indicators (KPIs) and stay focused. This also requires preparing a budget and schedule and measuring against this. Contract management, reports and reviews are part of the implementation. Several case studies are given as examples of the implementation of process design changes to highlight the critical aspects involved.

Jan 1, 2009

One of the strategies introduced within Pasminco Mining to survive low commodity prices is to formally implement a `Quality Education System'. The net result has been a consistent approach to quality within and across mine sites. This `quality system' has been adopted in the technical computing environment and the immediate benefits have been: ò A clearer understanding of the systems, processes and relationships that involve technical computing. ò A re-focussing on customer (user) requirements. ò Inclusion of managers as customers with their own requirements of performance and quality, in addition to access to Executive Information. ò New ways to measure the `performance' of a technical computing environment which includes using maintenance costs. Observations are that there is an overlap between `traditional' information technology (IT) methodologies and quality systems being put in place in the broader workplace. This overlap is most apparent in the area of analysing customer requirements. In the IT environment customers are viewed as users, and their requirements determined by undertaking a requirements analysis. A data flow diagram traditionally used in the IT environment and not as a tool in quality systems, has been used in a novel manner to help identify the customers of the technical computing department. It has also been useful in illustrating the work processes and relationships between the entities in this diagram and in directing the future initiatives needed to fulfil the customers' changing requirements.

Jan 1, 1995

By Taylor G. R

Fluid inclusions within quartz accompanying several stages of mineralization at Hillgrove are de cri bed. Pyrite-arsenopyrite-gold mineralization shows uncorrected filling temperatures of between 195°C and 250°C. Later stibnite-antimonide-siderite and stibnite-calcite mineralization has filling temperatures between 100°C and 195°C and a bimodal distribution of temperature peaking at 175°C and 145°C, possibly correlated with the two stages of mineral deposition. Secondary included fluids within an earlier generation of deformed quartz veins are derived from hydrothermal fluids contemporary with the main-stage mineralizing fluids described above. Primary inclusions within latestage, cross-cutting quartz-chlorite-calcite veins show these veins to be unrelated to the mineralization.A correlation between filling temperatures and salinities indicates that mineralization accompanied the mixing of a hot, partly saline, fluid (at 5 per cent equivalent NaCI) with cooler, less-saline meteoric or connate water. Over a vertical distance of 200 m, equivalent mineral assemblages were deposited over the same temperature range. Studies on single crystals suggest rapid deposition with fluid temperature dropping 45°C during their growth. Ore mineragraphy and the fluid inclusion data suggest that the metals were transported by sulphur-poor, relatively low-temperature, low-salinity solutions, possibly as carbonate complexe , and that a vertical zonation of the W-Sb-Au mineralization is compatible with the mixing of this hydrothermal fluid with cooler groundwater. Regional metallogenic and geological considerations suggest that ore metals are derived from the remobilization of deep-seated stratabound deposits or from metamorphic fluids expelled from deepseated volcanoclastic sediments.

Jan 1, 1984

By J D. St George

Flyrock is the unexpected and undesirable projection of rock fragments during detonation of a blast and managing this risk is becoming an increasing challenge as urban development encroach toward mineral extraction sites. The basic factors associated with flyrock are discussed in relation to geology, blast design and management. Published data of historical flyrock events are investigated and compared with local information on incidents. Good agreement was found between the data sets. A computer program of flyrock was developed using projectile motion based on launch velocity and angle, rock size, shape and density. This deterministic model was coupled with a probability model to simulate blast events. The impulse time ?t of the explosive pressure was taken as the stochastic variable to replace launch velocity. The variables were calibrated to replicate field data. A simulation was executed to demonstrate the capability of the approach to defining flyrock danger zones. For a simplistic situation it was identified that an appropriate distance to be cordoned off for the blast danger zone is a radius of 120 m in front of the blast and 65 m behind.

Jan 1, 2001

The areas of impact when employing high productivity long wall systems are reviewed and the financial implications of the most significant areas highlighted. A distinction has been made between availability and utilization. The need for more efficient delay recording, together with increasing control and utilization of the systems has been identified and the measurability of the latter discussed. The increased use of electronic delay reporting direct from the operating unit as the basis for operational control and a pre-emptive maintenance philosophy is seen as an important area of achieving higher performances from existing long wall production systems and Configurations.

Jan 1, 1988

By G W. Scott, H M. Lukey

The Lake Superior Region has been a producer of iron ore for over 150 years. Early mining operations concentrated on direct shipping ores, which are the result of post-depositional upgrading principally by deep weathering. As direct shipping ore reserves became depleted, the focus changed to the production of iron ore pellets from taconite. The post-depositional processes responsible for upgrading taconite are regional metamorphism, contact metamorphism and hydrothermal processes (Clout and Simonson, 2005). While these processes are important in iron ore genesis they can also contribute to liberation problems and in some instances reduced pellet quality (Han, 2004). Low-grade metamorphic mineral assemblages can negatively impact liberation and pellet quality. Low-grade iron formation may contain a suite of carbonate minerals including ankerite, dolomite, kutnohorite, siderite and magnesiosiderite. Variation in the distribution and composition of siderite and magnesiosiderite makes controlling the MgO content of pellets difficult. Carbonate minerals also require calcination in the pellet induration process, which requires additional heat to be added to the system, slowing down the induration process and reducing throughput. Prediction of carbonate mineralogy and carbonate mineral chemistry is an important goal of ore characterisation for pelletising properties. Contact metamorphism causes changes in mineralogy and grain size (Klein, 1973; Gunderson and Schwartz, 1962). Increasing the grain size of magnetite should improve its liberation characteristics. However, plant grinding targets may not allow the coarse-grained, more easily liberating magnetite ores to increase throughput and can actually result in decreased throughput due to recirculation. While magnetite and martite ores are well understood (Lukey, Johnson and Scott, 2007) late open-space filling microplaty haematite ores are not. These ores, while composed of similar minerals, have a unique genesis that results in fine grain size and complex textures that present liberation challenges and often make interpreting laboratory metallurgical test results more difficult.

Jan 1, 2007

By P Holt, M Allen

On the first of July, 2012, the Australian GovernmentÆs Clean Energy Act commenced. From this point, a price of $23/t of CO2-e will apply to facilities that trip the liability threshold. This first part of this paper concentrates on the mechanics of the Clean Energy Future legislation and how it will be applied to the mining and mineral processing industry.The second part of this paper contains analysis of the data presented for typical mine operations. Methodologies for constructing a carbon strategy are also presented. This will entail determining what the objectives of the carbon strategy are, and defining what the strategic priorities for a business should be. An action plan to address the risks identified from the Clean Energy Act is also developed as part of the strategy.Details such as the advantages and disadvantages of opting into the carbon price scheme for liquid fuels are shown. Other considerations such as the ability to acquire permits through the carbon farming initiative or through overseas clean development mechanism projects are explained.CITATION:Allen, M and Holt, P, 2012. Implications of the carbon price and developing a carbon strategy, in Proceedings International Mine Management 2012, pp 105-114 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

The new legislative regime applying to the mining industry has been in force for nearly two years. However the parameters for the permits required under the Crown. Minerals Act 1991 and the resource consents required under the Resource Management Act 1991 are still being established. Mining operators will benefit from participating in the development of policies and plans currently being formulated by local authorities. The Energy Legislation Amendment Bill currently before the House contains amendments to the Crown Minerals Act to clarify points of uncertainty and to reduce transaction costs where possible.

Jan 1, 1993

By A-A Latscha, C Boyle

Geological modelling has historically been done using sectional interpretation of paper sections or on a computer screen. Boundaries of geological units or grade shells are interpreted by a geologist section by section and the shapes are drawn onto paper to be digitised later or they are directly digitised into a computer. This approach is referred to as explicit modelling. Such methods are time consuming if there are many section lines or boundaries to be interpreted. The number of metres drilled and resource models made is increasing each year and it will be difficult to keep up using explicit modelling methods. Alternatively, it is possible to use information carried in the drill holes, known geological relationships and point estimation methods in two or three dimensions, to create similar geology boundaries, while eliminating or at least greatly reducing the need to manually interpret and digitise detailed sectional interpretations. Such methods are referred to as implicit modelling and are available in a number of software packages. Implicit modelling approaches have been used in iron ore and found to significantly reduce the time needed for modelling while producing results that are comparable or better than standard explicit modelling approaches. A number of case studies have been undertaken of implicit modelling in iron ore deposits. Stratigraphic surfaces of bedded, folded and faulted iron ore deposits have been modelled in various deposits by Leapfrog Geo, GOCAD (with SKUA) and Vulcan Integrated Stratigraphic Modelling. Leapfrog Mining was used to model iron grade shells at particular cut-off grades. The modelled surfaces are of a high standard equivalent to those that could be produced by traditional explicit modelling but the time required by the implicit methods is far less. Implicit geological modelling is an active area of software development and improvements in software are likely.CITATION:Boyle, C and Latscha, A-A, 2013. Implicit geological modelling of iron ore deposits, in Proceedings Iron Ore 2013 , pp 57-66 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By J Ireland, S Rose

The main outcomes of mining grade control include defining the boundary between ore and waste and then categorising the ore according to which stockpile it should be sent. A typical workflow includes using general mine planning software (GMP) – such as SurpacTM, VulcanTM or CAE StudioTM – to create three-dimensional wireframes of mineralisation domains, which are used to flag the relevant samples of interest and constrain estimation during block modelling. Creating the wireframes is a time-consuming process, requiring reasonable software skills, patience and an eye for detail. The interpretations can be subjective; indeed, even the same geologist will give different shapes if presented with the same data at different times. The process can become particularly tedious when trying to carry out updates due to new data. It can also be difficult to test the effect of alternative interpretations or grade thresholds because of the time constraints in production.There are now several implicit modelling tools available, either as standalone programs or as add-on modules to existing GMP. In this paper, the authors develop a workflow using implicit modelling methods to show how grades and geology can be rapidly interpreted to provide effective domains for grade estimation. The paper includes case studies from open pit gold mines. The implicit modelling approach can save several days of interpretation work for each grade control drilling campaign.CITATION:Rose, S and Ireland, J, 2014. Implicit modelling applied to grade control data, in Proceedings Ninth International Mining Geology Conference 2014 , pp 115–122 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By M J. Gillespie, P D. Erskine

Mine site rehabilitation generally includes the re-shaping of overburden to create a final landform, manipulation of substrates and subsequent revegetation. Due to the wide range of environmental variables that influence rehabilitation progression, having clearly-stated final land-use goals and ongoing significant contributions to the planning process, from prefeasibility through to mine closure, is essential for achieving stable landforms and sustainable rehabilitated communities. Two examples of rehabilitation processes in the phosphate rich region of North West Queensland are used to illustrate some of the possible benefits of early planning and communication of rehabilitation requirements.Approximately 160 km south of Mount Isa, Incitec Pivot Limited operates a 35 year old open cut mine at Phosphate Hill. Monitoring of rehabilitation areas and selected analogue sites is undertaken annually, but the initial landform design, substrate management and species selection has created a difficult environment for revegetated areas to successfully establish. Constant management input (such as weed management, erosion control, supplementary seeding, etc) will, therefore, be required over a long time frame.The second example uses exploratory drilling and historic costean pits at Legend International HoldingÆs Paradise South site, 135 km north of Mount Isa, to determine the success of natural vegetation colonisation on waste rock and compacted soils, and the effects of cattle grazing on recolonisation. This information can be used by planners of the mine life to inform possible end-land use decisions and proposed completion criteria.In a semi-arid environment such as North West Queensland, the creation of a post-mine landscape suitable for nature conservation and/or grazing can be an arduous task. The input from environmental personnel at all stages of the mining process will positively impact upon the quality of the resulting rehabilitation and ensure undesirable legacy issues are minimised.CITATION:Gillespie, M J and Erskine, P D, 2012. Importance of early rehabilitation planning - Case studies from North West Queensland, in Proceedings Life-of-Mine 2012 , pp 187-196 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By N Guresin, A Cooper, L Lorenzen, H Muller, S C. Dominy

Sampling and metallurgical test work during various phases of engineering?studies?is of?paramount importance for a robust processing plant design. When developing a process flow sheet, risks in achieving desirable financial outcomes are minimised by ensuring appropriate sampling and adequate metallurgical test work supports the engineering and cost estimation at each phase of project development.The quality and type of samples used for metallurgical test work are just as important as the metallurgical test work itself. The key characteristic required of any sample is that it represents some defined portion of a mineral deposit. Representivity should take into account the spatial orientation, lithology, alteration, degree of oxidation, mineralogy and competency of the ore such as hardness and abrasiveness. Statistically representative sampling procedures and an appropriate metallurgical test work program should be designed to bring metallurgical understanding up to feasibility study standard and to give a basis for process plant design.Snowden has observed that the quality of sampling and quantity of metallurgical test work carried out during the various phases of engineering studies are often insufficient to truly support a robust plant design. Some designs are often the result of the plant design based on benchmarks of apparently similar orebodies or buoyant metal prices supporting cash flows until rectifications can be implemented.The paper will discuss important aspects of sampling and test work required for engineering studies in designing process plants based on industrial case studies.CITATION:Guresin, N, Lorenzen, L, Dominy, S C, Muller, H and Cooper, A, 2012. Importance of effective sampling and test work protocols for process plant design, in Proceedings Sampling 2012 , pp 95-108 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 21, 2012

Gold recovery by catalytic copper ammonium thiosulphate solution has been studied. Such a process strategy is very attractive for leaching certain difficult-to-treat ores and presents lessened lixiviant toxicity compared to cyanide. Newmont Gold Company has evaluated the ammonium thiosulphate heap leach process for gold recovery from low-grade carbonaceous sulphidic refractory ores following biooxidation. The ammonium thiosulphate leach process has been studied in laboratory, pilot plant and demonstration scale. Satisfactory test results support the continuation of process development. However, the thiosulphate leach chemistry was found to be very complex. Maximum control of the stability of the leaching system is a key factor for success, especially for the heap leach process. Important solution chemistry is discussed in this paper.

Jan 1, 1997

Importance of Strain to Fragment Strength in Blasting Induced Pre-Conditioning When a rock is blasted, cracks propagate through the rock causing the rock to fracture. This paper focuses on applying the results from a series of small scale blasting tests were designed to show the effect that varying blast variables such as explosive type and explosive energy have on the resulting strength of the post blast fragments. It was shown that the velocity of detonation of the explosive product affects the reduction of fragment strength. This has important implications for the downstream comminution process. The observations from these tests are then explained with reference to the principles of fracture mechanics. A simple but effective prediction of blast induced preconditioning is shown.

Sep 13, 2010

By D Reid

The engineering properties of soils and tailings often exhibit significant anisotropy. One area where this has been well documents is undrained shear strength. Materials sheared in directions close to the principal stress direction in situ, i.e. triaxial compression, typically exhibit higher undrained strengths than those sheared in other directions such as simple shear. Importantly, along the most common critical failure surfaces relevant to tailings stability, whether primarily through tailings or a critical foundation layer, saturated materials are generally much closer to the simple shear loading direction than triaxial compression. Therefore, testing undrained shear strength of tailings or foundation soils in triaxial compression is likely to result in overestimation of the relevant strengths for design. Although these issues have repeatedly documented in the geotechnical literature for over three decades, they are not appreciated sufficiently across our industry. In an attempt to address and highlight these issues, a review is carried out of historical reference to the importance of simple shear loading. Attention is then drawn to the techniques applied in three recent post-failure investigations, where simple shear testing was applied. Finally, some relevant laboratory test results from a recent project in which the author was involved are outlined.CITATION:Reid, D, 2018. Importance of the simple shear loading direction to the stability of tailings storage facilities, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 274–284 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By C E. Loo

The cohesive zone has a significant influence on blast furnace operation and performance. The high-temperature behaviour of the reducing ferrous burden determines the properties of the cohesive zone and is studied in a laboratory using a softening and melting test. This paper summarises recent work aimed at better understanding the physico-chemical changes in a ferrous bed during softening and melting. Using a combination of standard, non-standard and quenched tests supported by optical image analysis, this work has highlighted some important differences in behaviour between lump, pellets and sinter as well as between the two lump ores and two acid pellets. As with the two lump ores, one pellet is denser than the other and the denser ore/pellet is also higher in silica.Within the cohesive zone, densification of the ferrous layer leads to reduced permeability and greater pressure drop. From the work presented in this paper, two key mechanisms of ferrous layer densification were identified. Firstly, the formation of fayalite, which melts at low temperatures, can act as a lubricant between particles and lead to densification of the ferrous layer under load. Secondly, reduction to metallic iron is topochemical and fayalite in the outer shell of the particle restricts gas flow to the centre and results in the formation of a wustite core. As temperatures rise, the wustite melts and eventually exudes out of the shell, occupying void spaces between particles and further reducing layer voidage and permeability.This work has shown that density and silica content are two key factors that result in increased densification of the ferrous layer. For porous Australian lump ore, the higher porosity and lower silica reduces the formation of fayalite and limits the formation of the wustite core, ultimately leading to a more permeable bed. The difference between the porous and dense ores was more pronounced with the introduction of prereduction to better simulate blast furnace conditions. This suggests that a porous ore gives significantly better cohesive zone permeability and blast furnace operations than a dense ore.The behaviour of fluxed sinter particles is different in that the silica reacts with lime to form dicalcium silicate. Minimal wustite core forms because relict hematite particles in sinter are only small and reduction occurs uniformly throughout the particle. Even with significant loss of material through prereduction, beds formed from sinter remained comparatively rigid. Studies using a typical blast furnace burden mix of 80 per cent fluxed sinter and 20 per cent porous ore showed that the structures of these beds at softening and melting temperatures are very similar to the sinter-only test. Measurements of bed contraction and pressure drop also confirmed that the introduction of 20 per cent porous ore into a sinter bed did not alter its properties. This is an indication that 20 per cent ore can be easily accommodated by blast furnace burdens.CITATION:Loo, C E, 2015. Important acid ferrous burden properties in the cohesive zone of a blast furnace, in Proceedings Iron Ore 2015, pp 367–376 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By Kellerwessel H, Oberheuser

Since its invention by Professor Klaus Schonert of the University of Clausthal, Germany, high pressure rolls comminution has attained near total acceptance as the preferred method of size reduction in the cement industry. Over 300 units have been manufactured worldwide. At locations where the system has been installed, considerable energy savings have been realised. These energy savings are generally in the range of 20 to 30 per cent compared to conventional ball mill circuits. However up to 50 per cent power saving has been achieved at some installations. This technology, with the exception of the diamond industry, has up to now had only limited success in ore processing. This has mainly been attributable to the abrasiveness of ores encountered in this industry leading to high wear rates. These high wear rates have given rise to an unacceptably short life time of the wear surface of the rolls, requiring regular replacement. A new wear surface has been developed which has shown to give a ten-fold increase in service life over conventional surfaces. This, together with developments made in machine design now give the units the ability to attain the high availabilities demanded by the mining industry, and therefore to allow this industry to achieve the considerable operating cost savings offered by the high pressure rolls.

Jan 1, 1992

By L D. Redden, M G. Nelson

Mechanical flotation machine design is typically based on hydrodynamic analysis, with scale-up calculated by geometric proportionality. End users often specify and purchase machines on the basis of retention time, characterised by the æ$/m3Æ approach; they may also consider the manufacturerÆs installed base. In some applications, end users also consider specific energy and the impact of energy consumption on operational costs. In other cases, a decision may be based on machine type (forced-air versus self-aspirating) and perceived metallurgical or operational advantages of one machine type over the other. With regard to metallurgical performance efficient bubble-particle contact is very important and is primarily influenced by two factors:the concentration and size distribution of bubbles in the machineÆs contact zone (the volume enclosed by the disperser); and the number of times that slurry is pumped through the contact zone. The second factor is a function of the machineÆs pumping rate and its retention time. Field data show that pumping efficiency is independent of aeration rate. In this paper, a new dimensionless number for the characterisation of flotation efficiency is presented. The contact frequency number (CFN) is defined as the number of times a given volume of slurry passes through a machineÆs active contact region, and is given by: CFN Qp/Qf, where:Qpis the pumping rate through the contact regionQfis the volumetric feed rate to the machine

Jan 1, 2005