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By J Pan, Q H. Li, D Q. Zhu, C C. Yang, X Wang, Z Q. Guo

Al2O3 in natural iron ores generally occurs in goethite, kaolinite, gibbsite, hematite and iron carbonate. When the content of alumina in sinter increases from 1.11 per cent to 3.50 per cent, the reducibility of sinter decreases with the addition of four different types of alumina. When gibbsite and kaolinite are added, the low temperature reduction disintegration (RDI+3.15 mm) of sinter increases with the increase of Al2O3 content in the range of 1.5 per cent to 3.5 per cent. Furthermore, when adding pure reagent alumina, the increase of Al2O3 content in the range of 1.5 per cent to 3.0 per cent will increase the RDI+3.15 mm of sinter. The addition of ferric oxide–alumina spinel with the Al2O3 content in the range of 1.5 per cent to 2.5 per cent, also increases the RDI+ 3.15 mm of sinter. The influence difference is results from the change of the mineral composition and microstructure of sinter because of the occurrence state of Al2O3. Under the condition that Al2O3 content of sinter is 2 per cent, the porosity of sinter with kaolinite is 37.26 per cent, and the shape is irregular. When gibbsite and ferric oxide–alumina spinel are added, the porosity of sinter is about 16 per cent, and the pores are round. When pure reagent alumina is added, the porosity of sinter is 17.49 per cent, and the pores are regular and small. When kaolinite, gibbsite and ferric oxide–alumina spinel are added, platy calcium ferrite is mainly formed in the sinter, and some of it is columnar calcium ferrite. On the other hand, when pure reagent alumina is added, in addition to platy columnar calcium ferrite, acicular calcium ferrite is also formed in the sinter.

Nov 8, 2021

By G R. Hancock, J F. Martín Duque

Post-mining landscapes are required to geomorphologically and ecologically integrate with their surrounds (Martín Duque et al., 2015). Designing and constructing an erosionally stable landform is the first and arguably most important part of the rehabilitation process. Without an erosionally stable landform topsoil and nutrients are lost, shallow groundwater is depleted as well as when excessive erosion occurs, expose suboptimal materials. Here we examine the ideas of geomorphic design and rehabilitation and how the landform can be tested and enhanced using computer based design and landscape evolution models. Specifically we evaluate the complementary capabilities of landscape modelling (SIBERIA) (Hancock and Willgoose, 2017) and geomorphic design software (Natural Regrade with GeoFluv) (Bugosh et al., 2016), in order to maximise erosional stability on post-mining landscapes (Zapico et al., 2018). CITATION:Hancock, G R and Martín Duque, J F, 2018. Geomorphic design and landscape evolution modelling for best practice mine rehabilitation, in Proceedings Life-of-Mine 2018, pp 119–121 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By MáAndrusiewicz, M M. Hilden, M S. Powell, P D. Kay, B Foggiatto

Circuits with unconventional and potentially more complex designs are predicted to become more common in the future as plant designers and operators look to process ores more efficiently. Ideas have been presented on how circuit design may be changed to utilise todayÆs technology to address tomorrowÆs challenges (Powell and Bye, 2009; Powell, Benzer and Mainza, 2011a). High pressure grinding roll (HPGR) installations in various configurations; application of preconcentration plants eg sorting, magnetic or gravity separation; and preweakening devices eg microwave processing; are all examples of technologies having the potential to deliver a significant reduction in comminution energy for ores amenable to these processes. Not only will future novel circuits contain equipment for which models are not as well developed (if at all), many will likely require the ability to respond to variations in feed, and interact with geometallurgical models requiring process adjustments when the ore characteristics change.In order to confidently simulate more complex circuits and accommodate variations in feed type, a significant advancement in modelling and simulation capability is required. This includes dealing with multiple components in the feed, accommodating different competencies of ore, utilising physical separation opportunities and tracking the grade reporting along the different potential processing routes. Developing the means to simulate complex circuits has been a key priority of a collaborative group of comminution researchers working to solve these challenges.Simulations are presented utilising a new configurable simulation interface called the model developers kit (MDK). The MDK is designed to accommodate multi-components and incorporate new models under development. These will be used to demonstrate the potential of flexible circuit design, based on measured ore properties and equipment performance.CITATION:Foggiatto, B, Hilden, M M, Powell, M S, Kay, P D and Andrusiewicz, M, 2012. Simulation of flexible circuits, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 291-298 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By D Walker, A Tsvetkov, P Voigt, O Kloiber-Deane

The GPM Gold Operation has been employing an Albion Process™ plant at its Sotk (Zod) gold mine in Armenia since 2014. Long term data from the operation is now being published for the first time. The data presented includes concentrate throughput, as feed to the Albion Process™ plant (tonnes per day), sulphur grade in concentrate (% S), total sulphide sulphur oxidation in the Albion Process™ plant (% SOx) and gold recovery from Albion Process™ plant residues (%). The data provides a basis for evaluation of the effectiveness of the commissioning, ramp up and operation of the Albion Process™ plant. Notwithstanding the impact of a slower concentrator commissioning than expected, the plant demonstrates Series 1 behaviour on McNulty ramp up curves, indicating successful commissioning and fast ramp up. Interrogation of the data and operational experience indicates that this successful operation is a result of a process that is flexible, robust and stable, one that was designed well based on solid testwork results and pilot plant trials during the study phase undertaken by Glencore Technology and Core Resources, and where the local operators were provided with appropriate training in operation of the plant. CITATION:Voigt, P, Walker, D, Kloiber-Deane, O and Tsvetkov, A, 2018. Ramp-up and long-term performance of the Albion Process™ plant at GeoProMining Gold Armenia, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 339–350 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By D Semini, B Newcombe

Base-metal sulfide refractory gold ores often contain a portion of ‘free’ gold that is amenable to recovery using gravity concentration methods, whilst the refractory portion of the gold is better recovered using flotation. The decision as to whether a plant treating a refractory gold ore should utilise gravity concentration or a flash flotation circuit (or a combination of both) within the grinding circuit is usually made at the design stage of flow sheet development. Very limited data is available in the published literature which provides an industrial scale comparison on which to base such a decision and conventional laboratory testing methods are often the only way of obtaining such data. The optimum processing route will also be mineralogy dependent.This paper presents the findings of operating a refractory gold plant with either flash flotation (normal operation) or a combination of flash and gravity recovery methods treating the cyclone underflow stream and will demonstrate the regions of the recovery profile that each contributes to. Size-by-assay analysis has been performed on a number of streams around the operating plant to gain an insight into the changes that occur when the gravity circuit is in operation in addition to the flash flotation circuit. A discussion around the implications to overall plant operation in combining the use of a batch process (gravity concentration) with a continuous process (flotation) is presented.CITATION:Newcombe, B and Semini, D, 2014. Interactions between flash flotation and gravity concentration – an industrial case study of a refractory gold concentrator, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 427–436 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By J M. Wallis

Heavy mineral sand exploration drilling prior to the 1970s generally utilised open hole auger and air-blast type drilling. However, mining reconciliations were poor and limitations on accuracy and precision of drilling results were severe.Working with the exploration companies, Wallis Drilling principals designed various systems, including what was termed the ‘Eneabba System’ and then the ‘Capel Twin-Tube System’. Eventually the company with its improvements developed and patented the Aircore Drilling System.Aircore drilling has subsequently become recognised as an excellent drilling system for exploration and mine-sample drilling that gives good precision and accuracy in sampling both above and below water. Its use has also been extended to many other commodities and is used in a number of overseas countries.This paper documents anecdotally the development of the system, identifying problems encountered during the times it was evolving and of the means to overcome the problems as being the documentation of the story by the inventors and developers in Wallis Drilling Company. Aircore drilling system is a Western Australian technological development owing its existence to the designing and incorporation of a number of discrete improvements along the way and recognises the tenacity and inventiveness of all who contributed to the system, in both Wallis and also in a number of companies that gave the impetus to succeed.

Oct 5, 2011

By T Ireland, S Eratne, W Newns, P Spies

The approach to risk management during the procurement of major projects often has a significant outcome on the ultimate delivery of a project. The NZ$1.4 B Waterview Connection project is the largest and most complex project yet undertaken by the New Zealand Transport Agency (NZTA) and the procurement process for an alliance contract was refined to provide compliance with the International Tunnel Insurance Group (ITIG) Code of Practice for Risk Management of Tunnel Works (TCoP). The principle of shared risk within an alliance incentivises a common understanding of project risks prior to finalising the alliance agreement and therefore enables superior risk management through design, construction and beyond. Risk management practices need to be instigated well in advance of commercial phases, so that commercial competition does not lead to a significant elevation of project risk. In particular the practice of gaining commercial advantage by taking on a potentially unmanageable level of risk is one of the outcomes to be avoided by the TCoP.During the procurement phase the NZTA placed high value on design and construction mitigation measures proposed in order to address ground risks, as is appropriate for a major tunnel project. In order to achieve alignment on the level of geotechnical risks an Alliance Geotechnical Baseline Report (AGBR) process was developed.This paper describes the measures taken during the procurement process to achieve certainty with respect to outcomes and minimise project risks whilst also achieving value for money. Refinements to the procurement process to ensure compliance with the TCoP prepared by the International Tunnel Insurance Group (ITIG) are described along with the AGBR process applied as part of a suite of measures to achieve a successful procurement outcome.CITATION:Ireland, T, Spies, P, Eratne, S and Newns, W, 2014. Risk management and use of a geotechnical baseline report for a competitive alliance procurement?process, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 553–562 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

Real-time data collection and plant historians are becoming common place in mining and processing plants. This vast quantity of data must be turned into easily accessible and actionable information for all levels of the organisation.Queensland Nickel use a combination of Microsoft and SAP business intelligence tools to collect, cleanse, aggregate and present plant information to the appropriate people for supporting decision making in the business. SAP Business Objects, for visualisation, and SAP MII, for integration, allows complex and accurate metrics to be delivered as real-time dashboards. Designing a rigid data management architecture to segregate the data collection, integration and logic and visualisation into distinct logical layers, allows for rapid report development and greatly assists with IT maintenance, while also minimising the complexity of any customised programming. This type of architecture ensures a common data source for all business reports, ensuring one version of the truth. The past few years at Queensland Nickel have seen process and maintenance engineers spending considerably less time collecting and integrating data and spending more time analysing what is happening in the plant. Real-time reports and dashboards have been developed around the business needs rather than around the data. Two years ago Queensland Nickel introduced an employee bonus scheme based upon meeting monthly performance targets; an easy to use dashboard that allows everyone, from operators through to management, to monitor these metrics day-to-day.

Sep 26, 2011

By D T. Ribeiro, J F. C L Costa, J C. Koppe

Drilling and sampling are responsible for most of the costs during mineral exploration, especially in multi-elements and polymetallic deposits, such as iron, manganese and bauxite deposits. On these deposits, often it is necessary to estimate multiple attributes at several granulometric fractions, ie distinct particle sizes. This paper investigates the effect of sampling at a close spacing grid only the head grades for the multiple chemical species in iron ore deposits. The remaining required data at the various grain sizes are sampled at a sparse grid. The derived geological model is checked for precision and accuracy comparing the output obtained against a model obtained using a complete isotopic data set including head grades and chemical analysis at each granulometric fraction analysed at all sampled positions. Among the several tested alternatives, the best procedure for dealing with the posed problem involved utilising the correlation coefficients between the grades at distinct fractions to obtain an isotopic database prior to interpolation. Cokriging was the method used, based on the intrinsic coregionalisation model. Estimates were obtained with the quality needed for the proposal of the study. Results showed that at least 50 per cent of the blocks were estimated with errors less than ten per cent relative to the grades obtained at the reference model, using only 15 per cent of the granulochemical data employed to obtain the reference model. The methodology also preserved the correlations between the attributes in their several granulometric fractions on the estimated model.

Sep 26, 2011

The Gold Ridge Mine is an open-cut gold mine in the Solomon Islands. The mine is owned and operated by Gold Ridge Mining Limited, a wholly owned subsidiary of Ross Mining NL. At the invitation of the Solomon Island Government, project construction commenced in July 1997 and gold production commenced in August 1998. The mine is the countryÆs first, and represents a major milestone in the development of the Solomon Islands. At the time of project approval and construction, there was a growing awareness in the country of the potential impacts of mining in the tropics, partly due to unfavourable publicity surrounding a number of other mining operations in the Pacific region. The management of environmental impacts was therefore an important consideration in the approval of the project, and continues to receive a high level of attention from the Government and community. Ross Mining did not commit to the Gold Ridge Project until it had satisfied itself that all waste rock and tailings could be safely contained on-site, and that the standards normally expected of a mine in Australia could be met. Ross Mining approached the approval, construction, and operation of the Gold Ridge Mine with a set of operating principles that met Government and community concerns. These were:best practice environmental management; operation of the mine in accordance with standards expected of mining operations in Australia; independent peer review of key technical aspects; on-going consultation with Government and community; and equitable transfer of wealth to landowners and the local community. As a consequence, the Gold Ridge Mine has developed into a successful mining operation with a high level of support from local landowners, the general community and the Central and Provincial Governments of the Solomon Islands.

Jan 1, 1999

By M Nagarajan

Orica Mining Services (Orica) in partnership with Coal and Allied’s Hunter Valley Operations (HVO) has developed a risk management process to maximise mining efficiency whilst controlling vibration and maintaining critical electricity continuity to New South Wales (NSW) electricity grid in the Riverview Pit. The issue is a high tension tower which supplies electricity located within 40 m of mining and blasting activities. The process involved developing an understanding of the relationship between vibration, explosives, geology and the location of the blasting in the geological horizon. From this an optimum methodology for blasting in each region was developed.

Nov 8, 2011

By Schaap W

A test on Taylor's rule of mine life using published data on open pit porphyry copper mines confirmed that mine life is, on average proportional to the fourth root of reserve tonnage. Deviations from this rule-of-thumb occur to a large extent as variations between regions that are qualitatively explained in terms of differences in grade, infrastructural needs or special taxation effects.

Jan 1, 1984

By I R. Souza

At the mining industry, there are several uncertainties that may affect the mobile mining equipment fleet sizing and usage, such as commodity supply and demand, which impacts the mineral price, environmental licenses to allow operations and strategic decisions made by the own mining company. Due to that, it may happen to acquire a mobile mining equipment for a specific site and before it finishes the entire forecasted life cycle, the machine gets idle on that operation and a decision must be made regarding this matter. On large mining companies with several sites, equipment transfer provides a good solution to solve this issue and at the same time it provides operational flexibility and allows to use the equipment until the initially planned working hours. This article presents a method to compare technically and financially whether it’s more feasible to transfer a used equipment or to buy a new one. In other words, we will compare a brand-new machine versus a used one in terms of safety, net present value (NPV) considering both capital expenditures (CAPEX) and operational expenditures (OPEX), technological obsolescence, risks, equipment maintenance reliability and lead times. Although it’s not the main purpose of the paper, it will also be briefly discussed the importance of having a considerable amount of backup equipment to handle low likelihood and high consequence risks that may materialise. This backup equipment portfolio is particularly important to avoid loss of sales and profits in case the production plan changes and it demands further equipment than initially planned to cope with the forecasted production.

Nov 8, 2021

By C Augustin, M Hahn, K Nienhaus

Operators of mining machinery like haul trucks or excavators have very limited information about the exact distance to other equipment as well as to the natural boundaries like berms, walls and structures such as crushers. The industry is seeking solutions to provide safety and positioning. The authors have developed a solution approach which is being used in several installations. This solution consists of three parts: first robust and compact two-dimensional (2D) radar scanners that provide range and angular information of the environment especially under difficult conditions like dust, rain, snow and fog; second an intelligent data processing framework flexible enough to adopt to different machines and operation modes like speed, inclination, visibility, tire friction, GPS position, orientation and acceleration; and third a high quality and easy to use interface giving highly condensed data to the operator, not blinding the operator at night and being sunlight readable. The truth of present proximity detection sensors is that they not only have a high false alarm rate but furthermore cover only a fraction of the possible scenarios. This makes them unsuitable for stand-alone collision avoidance systems. On the other side, mine dispatch systems only deliver database and GPS information, but no information regarding the real environment. The indurad company and its Australian partner CTS (http://www.cts.com.au) addressed these aspects by developing smart productivity enhancement driver assistance tools like lane and crusher dumping assistance.An innovative driver assistance tool developed in cooperation with the coal shearer manufacturer Eickhoff and the RWTH Aachen University has been awarded with the annual research award of its customer RAG, being the largest German hard coal producer, as well as with the bauma Innovation Award in 2010.

Sep 26, 2011

By C Lower

An unprecedented, quantitative, deposit-scale understanding of major clay mineral distribution throughout the Yeelirrie uranium deposit has been achieved by adapting the existing HyLogger™/HyChips™ analytical technique to measure resource assay pulps. Spectral analysis via HyLogger™ and HyChips™ systems has previously been used as a small-scale geometallurgical research tool, but never before has it been quantitatively applied to an entire resource sample population for the purpose of developing stand alone block models for major clay minerals. Economic uranium mineralisation within the thin but extensive Yeelirrie?palaeochannel?primarily exists within the transition zone between a groundwater-derived calcrete and the underlying clay-quartz regolith. Early geometallurgical investigations identified that certain clay minerals could be deleterious to the efficiency of the uranium recovery process. Accurate calculation of clay mineralogy from resource assays proved too difficult due to chemical similarities between co-existing kaolinite, smectite and magnesium carbonate minerals. A relatively low-cost, efficient and accurate method of quantitative clay mineral analysis was required to measure over 70 000 resource assay pulps. After initial testing and comparison with QXRD, the HyChips™ 3-1 spectral logging system was implemented as a primary method of clay mineral analysis for the Yeelirrie uranium deposit. The resultant spatial data set allowed the interpretation and geostatistical analysis of geometallurgical domains across the deposit. Clay block models were generated and used in geometallurgical resource calculations to benefit the mine planning process.

Sep 5, 2011

By P Standish

Qualitative risk assessment methods are not well suited to considering complex systems and potential interactions of new technology. As part of supporting tier one mining organisations and international industry groups, the author and colleagues have innovated processes to help provide better solutions to sites/companies considering a move to implementing proximity detection and collision avoidance systems. The process identifies required operating states for the system. By applying a combination of research and team-based analyses, a rigorous identification of credible failure modes which could cause these states to be lost, is identified. Finally, required business inputs, expressed in practical terms are distilled from regulator, industry, organisation and site in a way which clearly addresses the failure modes and so retain the required operating states. These business inputs identify improvements for site arrangements (EMESRT levels 1 to 7) before identifying functional requirements for technological collision avoidance solutions (levels 8 for advisory and 9 for autonomous). The paper presents a case study synthesised from multiple sites analyses and will provide guidance on where to find additional resources to assist in making the best possible transition to better equipment and road network solutions.

Jun 22, 2022

By F H. Henrfquez, A G. Oroz

Design and operating conditions of large size mechanical flotation cells were evaluated by comparing them with actual operating conditions in a plant. The objective was to determine the time scale-up factor, typically based on empirical rules. Experiments were conducted on the rougher flotation circuit at Minera Escondida Ltd. The circuit consisted of self-aerated mechanical cells of 160 m3, arranged in six parallel banks with nine cells each. The rougher circuit flotation kinetics were evaluated from direct sampling and local mass balances around each cell of the bank. Adjusted overall mass balances were also developed. This information was used to fit different kinetic flotation models, and it was found that the rectangular distribution function was the most appropriate to describe the distributed rate constant for industrial operation. Then, a rougher flotation simulator was developed to describe the actual operation in terms of the operating variables (mass flowrate, solid percentage, feed grade) and the actual volumetric flowrate entering to each cell. In this study feed pulp samples were taken in parallel from the rougher circuit and were simultaneously floated in the laboratory. The kinetic behaviour was then modelled at a laboratory batch scale in order to determine the time scale-up factor between laboratory batch flotation data and industrial size flotation. The time scale-up factor observed for large sized cells, 160 m3, was found to be reasonably similar to those previously determined for self-aerated mechanical cells, but of lower size, operating at similar recoveries. In addition, the relative effect of mixing, between laboratory batch and an industrial flotation bank, was quantified by the parameter, separating the impact that kinetic and mixing changes have on the time scale-up factor. In general, the rougher flotation operation was found to reach the predicted metallurgical target, and the optimal separability criterion was also respected. The diagnostic generates information about the internal state of the process and helps to identify potential improvements for design, operation and control of the circuit.

Jan 1, 2005

By Q Zhuo, P C. Pistorius, M N. Al-Harbi

A likely increasingly important pathway for future low-carbon ironmaking and steelmaking is the combination of gas-based direct reduction with electric furnace steelmaking (DRI-EAF route), or with electric smelting (DRI-ESF route). In the DRI-EAF route, the gangue that is present in the iron ore is fluxed and removed as slag in the melting (steelmaking) step. This is in contrast with integrated steelmaking, in which the gangue is removed as part of blast furnace ironmaking. For DRI-EAF steelmaking, the amount and composition of slag depend on the iron ore composition, flux additions and iron yield. Slag volume and composition affect phosphorus removal, foaming behaviour and the process energy requirements. In this work, heat data from a year of DRI-EAF production was analysed to test whether the expected relationship between slag volume and electricity consumption for EAF steelmaking was observed. The data include slag analyses (one sample per shift), and heatlevel information on all inputs, final steel temperature and dissolved oxygen concentration, electricity consumption, tapped steel mass and tap-to-tap time. In analysing the data, the slag volume was estimated from the assayed slag CaO concentration and CaO inputs to the EAF. The expected effect of slag volume on steelmaking energy consumption was calculated with a mass and energy balance, considering the heat of mixing of the slag. The calculated energy requirement of slag formation is in line with previous estimates reported in the literature.

Aug 21, 2024

By G Chitombo, A Perryman, A D. Campbell, J White, B Hollis

This paper describes the development and implementation of an optimisation tool developed as part of the Mass Mining Technology (MMT) Project. The tool, known as the SLC Schedule Optimiser, is capable of optimising the schedule of development and production activity for a sublevel cave, given a fixed draw strategy, for the life of the mine.This paper starts by describing the development and production scheduling problem for a sublevel cave, the geotechnical constraint that a schedule of activities must adhere to, and outlines the pre-existing manual planning procedures used to produce schedules.Following this, the paper then outlines the optimisation tool developed, describes the changes to the planning process it has enabled and finally quantifies the improvement to operations this tool has brought using Glencore’s Ernest Henry Mining Operations as a case study.CITATION:White, J, Perryman, A, Campbell, A D, Hollis, B and Chitombo, G, 2016. Life-of-mine development and production scheduling optimisation for sublevel cave operations, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 133–138 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By S Szylkarski, D N. Graham

In mining, water management is an operational necessity, requiring planning and detailed engineering, as well as risk assessment. Yet, the hydrology of streams and aquifers typically extends well beyond the boundaries of mine operations and intersect with environmental and social values. Mine managers often plan, design and assess the impact of water management activities (such as dewatering, excess water disposal and flood management) with a mine site or process specific focus. The challenge is that the impacts are spatial, long-term and complex – and may be cumulative across multiple mine sites. Further, there is usually little consideration of the feedbacks and interactions between surface water, groundwater and catchment hydrology. Failure to understand these processes can lead to poor decisions and increased costs. This presentation outlines an approach to simulating integrated hydrology in mining catchments that addresses the shortcomings of traditional modelling techniques.CITATION:Graham, D N and Szylkarski, S, 2016. Simulating integrated hydrology in mining catchments from planning to closure, in Proceedings Life-of-Mine 2016 Conference, pp 101–105 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016