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Cannington Mine is an underground, hard rock, metalliferous mine located in North-Western Queensland, Australia. Weld mesh is installed to prevent the failure of rock from between the installed reinforcement elements. Corrosion reduces the capacity and life expectancy of mesh and presents a real hazard to underground personnel and equipment as it reduces the effectiveness of the support system. Corrosion influences the economics of the mining operation through the need to conduct rehabilitation of the ground support which involves re-installing new mesh or shotcreting over the affected mesh to protect it from further corrosion. The requirement for rehabilitation is determined by the geotechnical engineer based on an individual visual assessment with little or no engineering input. It was identified that a more quantitative method was required that considered the safety and economic risks involved. A project was undertaken to develop a simple method to evaluate corroded mesh and to provide selection criteria for rehabilitation. A weld mesh corrosion classification has been developed that relates the average wire diameter of corroded mesh to the remaining capacity of the mesh. Accompanying selection criteria provides recommendations as to when rehabilitation may be required based on the estimated residual mesh capacity, the remaining development life, and the level of personnel exposure.

Nov 25, 2010

By A B. Richards

A brick veneer house located on a open-pit coal mine lease has been subject to ground vibration levels of up to 222 mm/s, and air vibration levels of up to 145 dBL. The dynamic response of the structure was measured with accelerometers, geophones, and strain gauges as part of a project investigating the response of brick veneer houses to blasting. This paper outlines the project, and provides information on brickwork strength, foundation investigations, and observations on damage due to blasting. Correlations have been made between crack behaviour and factors such as blast vibration levels and rainfall.

Jan 1, 2001

By R M. Arellano, D M. W Harney, M Makhuvha

Mineral resource and ore reserve estimates are founded on two sources of data: tonnage and grade. The tonnage is a product of volume and density; both of which are estimates. Density impacts numerous operational factors, which include, but are not limited to, mine design, mine planning, equipment selection and operational performance. Hence, density is a significant parameter and its determination requires similar care as the measurement of grade. Selecting an appropriate method to determine density, and ensuring its rigorous application, thus reduces risk and can improve operational performance, which in turn increases profit margin.Different Anglo American sites use a variety of practices and protocols to determine density, which is highly dependent on the physical characteristics of the orebody, local conditions and historical practices. Also, individual sites sometimes execute the same method in a slightly different way, which may also affect the outcome of the measurements. In order to gain a better understanding of how density is determined at Anglo American projects and operations, a review of these techniques was undertaken. The objective of the study was to identify and share good practices across the company, as well as to look for improvement opportunities, where applicable. Ten different methods of measuring density, applied to nine different commodities, were identified and described. An additional technique was recently developed by Anglo American Technical Solutions. The core pycnometer is a large gas displacement pycnometer capable of measuring density at high accuracy on full pieces of intact core.This paper provides an overview of methods used to determine density within the Anglo American Group, including quality control and quality assurance aspects. It is not the purpose of this paper to identify a preferred method, but to highlight the importance of choosing the best suited practice for a project or mine site. In addition, a case study comparing two different density determination methods applied to the same rock samples from the Los Bronces Copper mine was undertaken and the results of that study are presented here.Selecting the most appropriate method to determine density and comparing results from two or more techniques against each other, together with other suitable quality control procedures, is considered to be of utmost importance for all mining operations and exploration projects.CITATION:Makhuvha, M, Arellano, R M and Harney, D M W, 2014. Determination of bulk density in Anglo American plc, methods and impacts, with a case study from Los Bronces Mine, in Proceedings Ninth International Mining Geology Conference 2014 , pp 85–96 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

By Iwu GO, Almond DP, Joasoo _

The gravimetric integral Knudsen effusion method was used to measure cadmium activity values in binary liquid In-Cd alloys in the range 523 to 573 K. The activity measurements together with other studies from the literature indicate that special bonding conditions exist in the melts near a composition corresponding to InCd3. Sound velocities in In-Cd melts were also measured using a precision pulse-echo over- lap method in the range 404 to 953 K. The frac- tional deviation of experimental and ideal isentropic compressibilities at 623K shows a functional dependence on composition with a pronounced maximum near the composition 75 at.%.

Jan 1, 1980

By C Zschiesche, alam, A Abadias Llamas, A K

An integrated experimental and thermodynamic modelling study of the phase equilibria in the FeOFeO1.5- SbO1.5-SiO2 system in equilibrium with liquid Sb and Sb-Ag metal has been undertaken to develop thermodynamic model of the Na-Si-Fe-O slag system with S-Sn-Sb-Pb-As minor elements based on the experimental investigation of the selected sub-systems. New experimental phase equilibria data at 575–1600°C were obtained for this system using high-temperature equilibration of synthetic mixtures with predetermined compositions in sealed silica ampoules, Fe3O4 basket in sealed silica ampoule, or Re foils, a rapid quenching technique, and electron probe X-ray microanalysis of the equilibrated phase compositions. Experimental results on phase equilibria in the Fe-Sb-Si-O+Sb metal system obtained helped to produce initial set of model parameters in the slag. The primary phase fields of quartz/tridymite/cristobalite (SiO2), 2 high-SiO2 immiscible liquids, olivine (Fe2SiO4), wustite (FeO1+x), spinel (Fe3O4), schafarzikite (FeSb2O4) and valentinite/ senarmontite (Sb2O3) were identified in the binary Sb2O3-FeO, Sb2O3-SiO2 and ternary FeO-Sb2O3- SiO2 systems. Further refinement, particularly the distribution of excess Gibbs energy among the ‘FeO’-Sb2O3-SiO2 and ‘FeO1.5’-Sb2O3-SiO2 interactions, required the study at more oxidising conditions. Oxygen potential was increased using an inert metal (Ag) rather than using the gas flow due to the high volatility of Sb-containing gaseous species. Liquid Ag-Sb alloys with low concentrations of Sb of a few percent were used. At these conditions, the concentration of AgO0.5 in slag was below 1 mol per cent, which had a small effect on observed phase equilibria in the system. In addition, important information on the solubility of silver in slags is produced, which can be valuable when treating electronic recycling materials or primary silver-containing ores through the Pb process. Two main areas were addressed: the spinel-tridymite boundary (40–70 per cent SiO2 in slag) and spinel liquidus near 15 per cent SiO2 in slag. This allowed to deconvolute the separate contributions of the FeO-Sb2O3(-SiO2) and Fe2O3-Sb2O3(-SiO2) systems.

Jun 17, 2024

By D Frost, G Harbort, T Lipiec, N Deonarain

"The use of flotation columns has remained a contentious issue among mill operators. There are those who consider them an essential part of any mineral processing operation, while others consider them a necessary evil, which should only be installed if there is no alternative. Lastly, there are those who believe they should not be installed, no matter how great the perceived benefit.This paper provides an analysis of over 4000 installed flotation columns, contained in the Amec Foster Wheeler flotation database. Changing trends in column flotation use by type, commodity and geographical region are discussed. The effect of changing commodity prices and the China ‘phenomenon’ are reviewed. Special reference is made to the changing face of column flotation in Australia.Of note is the fact that after falling to a 20 year low in installed flotation column capacity in 2014, flotation columns during 2015 went through a resurgence in popularity. This resurgence was in direct contradiction to depressed metal prices and was driven by brownfield optimisations to reduce off-site costs, particularly in base metals. A case study is presented comparing the benefits of column flotation at high commodity prices with low commodity prices.Citation:Harbort, G, Deonarain, N, Frost, D, Lipiec, T and David, D, 2016. Changing Trends in Column Flotation Use - Their Impact for Australian Mill Operators, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 93–104 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By Y Zhu, D J. Williams, M O’Neill, C Zhang, X Lei

A cover of inert material overlain by topsoil is required over compacted, seawater-neutralised red mud, a waste product from the refining of bauxite to produce alumina. The cover is to be revegetated, and it is necessary to demonstrate that the potential evapotranspirative-driven uptake of salts from the seawater-neutralised red mud will not impact the revegetation. An instrumented column was designed and constructed to test the evaporation-driven uptake of salts from compacted red mud into an overlying cover material with a thickness limited to 600 mm. The PVC column is 1.2 m high, with a 200 mm internal diameter. The column is instrumented with up to ten of each of moisture, suction, salinity and temperature sensors, together with a data logger, designed and manufactured at The University of Queensland (UQ) in Brisbane, Australia. The sensors were installed through the wall of the column at various depth intervals, with each set of sensors located at quarter points around the circumference of the column. Two pressure transducers were installed in the column to monitor the change of water level due to rainfall and evaporation. The column was filled with compacted red mud to a depth of 600 mm overlain by 600 mm of cover material, both sourced from the Queensland Alumina Limited (QAL) site in Gladstone, Queensland, Australia. The column is installed on a building roof at UQ, alongside a weather station, and will be subjected to the prevailing weather conditions for up to 1 year in the first instance, during which time the weather conditions and sensor responses will be continuously monitored. This paper reports on the instrumented column set-up and the early results obtained from the test.CITATION:Zhang, C, Williams, D J, Lei, X, Zhu, Y and O’Neill, M, 2018. Instrumented column testing of salt uptake from compacted red mud into a cover, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 220–226 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By C Beal, S Singh

Sensor-based bulk ore sorting is a form of preconcentration that autonomously measures and physically separates discrete bulk ‘pods’ of run of mine (‘ROM’) or primary crushed material. This case study examines the results of a full scale bulk ore sorting trial undertaken at Cozamin mine in Zacatecas, Mexico in 2019. The bulk ore sorting plant comprised primarily of a mobile jaw crusher, fixed conveyor, MR analyser, and diverter gate. Results of the trial demonstrate that bulk ore sorting could deliver a net improvement in copper metal fed to the processing plant of 6-8 per cent within an equal gross tonnage of ore. Copper metal increases were the result of improvements in mining recovery, where valuable mineralisation is recovered from marginal or sub-grade material that would otherwise be discarded as waste or stockpiled as low-grade. The increase in mining recovery more than compensates for metal losses suffered in the bulk ore sorting plant.

Nov 10, 2020

By P Odins

Traditionally, stratigraphic deposits have been represented by a large number of gridded surface and product analytical models, related to each other by naming convention. This approach, though suitable for structurally simple stratigraphic deposits, does not lend itself well to addressing the complex style of stratigraphic deposits which are becoming more prevalent. In addition, the sheer number of individual gridded models involved makes it very difficult to keep a consistent audit trail of the overall deposit model. Recently, a new enhanced block model structure known as Horizon Adaptive Rectangular Prism (HARP) models was introduced to address these issues. An HARP model is specifically designed to allow stratigraphic units to be represented with virtually no loss of structural integrity, by allowing the tops and bases of the individual HARP blocks to ‘bend’ in concert with the input surfaces. By bringing together the best of grid modelling, triangulation modelling, block modelling and grade estimation, the HARP model opens up many exciting new opportunities for the stratigraphic geologist or engineer to take their model further than was previously possible. Examples of improvements in modelling methodology using a HARP model include: the ability to represent complex normal, reverse and thrust faulting; the ability to store thousands of additional analytical, geotechnical or calculated variables in each individual block; advanced visualisation, manipulation and plotting capabilities; and the ability to calculate volumes and resources against complex, three-dimensional (3D) solid pit designs. Finally, several ‘real world’ scenarios, illustrating how this advancement in modelling technology can benefit a wide range of mining professionals are detailed. These examples demonstrate how productivity gains can be made in both long-term resource modelling and short-term ‘week by week’ geological modelling as an adjunct to mine planning.

Aug 22, 2011

By A R. Hollis, M Heddon

The safe life cycle of a Tailings Storage Facility (TSF) is founded on the fundamentals of proper design, construction, operation and closure. Leinster Nickel Operations (Leinster) utilises four active TSF cells that are cycled between filling (deposition), desiccation, and construction to meet a targeted rate of rise. This results in ongoing and consistent raising of the TSF walls. Critical to maintaining the safe life cycle through this consistent wall raising is precision construction and high frequency quality assurance to ensure compliance to design requirements and TSF walls free from defects. Leinster has recently deployed Intelligent Machine Control technology for TSF construction. Advances in Intelligent Machine Control have decreased variability in construction; ensuring variations are within the tolerances of design. The Intelligent Machine Controls are programed to ensure construction conforms to design tolerances of +/-30mm. This level of accuracy provides assurance of borrow area set out, compacted layers are as per design, compaction monitoring is within the zone placed, scarification between layers to prevent lamination is maintained, and batter angles are set to the correct grade. This level of control provides certainty that construction meets the design intent. In conjunction with Intelligent Machine Control, periodic drone surveys are conducted to verify construction against design. Advancement in survey equipment and techniques allow higher frequency, high accuracy survey to be completed on demand by site based personnel. This provides quality assurance through all stages of the construction phases, as well as the final constructed wall, ensuring compliance to design. Combining Intelligent Machine Control with higher frequency quality assurance provides an increased level of certainty that the TSF construction is defect free and within quality specifications. These recent technological advancements in Construction and Quality Assurance ensure cell raises are constructed to the design intent with greater levels of accuracy and precision than ever before.

Jul 1, 2021

A belt of serpentinized ultrabasic rocks intrudes a moderately folded geosynclinal sequence of fine to coarse sediments, acid, intermediate, and basic volcanics as well as a batholithic mass of granitic rocks. The ultrabasic body contains small included masses of melanocratic and leucocratic rocks, together with chromium, copper, zinc, and nickel mineralization.

Jan 1, 1969

By M Taylor

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

Mar 8, 2011

By D Yan, D Connelly

Beneficiation of magnetite is an integral part of the future of iron ore processing. Historically, the focus of Western Australian producers has been on exporting direct shipping ore (DSO) namely haematite. The future for new DSO resources is limited so companies are changing their emphasis into processing the very large, undeveloped magnetite ores in Western Australia (WA), using beneficiation to produce shippable magnetite concentrates. These magnetite resources require higher cost processing techniques such as fine grinding and beneficiation to produce saleable concentrates. This distinct difference, from the DSO ores, has led to the development of a number of new technologies. This paper reviews: the different techniques used for magnetite beneficiation and provides some case studies in the WA industry; the use of mineral liberation analysis (MLA) to describe the nature, grain size, occurrence and associations of the mineralisation;the consideration of coarse cobbing as a critical upgrading; the application of high pressure grinding rolls (HPGR) to save energy; how the field of magnetic separation has resulted in new machines with higher field strength (SLon Separators); ultra fine grinding requirements of magnetite concentrates; andthe application of reverse flotation to reduce silica in the concentrates.

Jan 1, 2009

By D J. Thobaven

Project financing challenges caused by declining commodity prices have heightened the need to improve project metrics such as minimising capital payback and maximising net present value (NPV). Khnaiguiyah Mining Company (KMC) recognised the need to improve early cash flows at their Khnaiguiyah zinc-copper project after initial studies showed the project could not provide the desired financial outcomes necessary to compete for investment dollars in the current market.A significant improvement to the project cash flow in early years was realised through simultaneous optimisation of cut-off grade, mining sequence and strategic stockpiling. This improvement was achieved by accelerating mining in the pits, stockpiling lower value material and feeding higher value material directly to the plant. The schedule required higher mining and stockpile capacities than the sequential mine plan although minimal change occurred in the definition of ore and waste as measured by tonnes and grade. The practicality of the strategic schedule was demonstrated by implementation in the production plan with excellent conformance.CITATION:Thobaven, D J, 2014. An application of simultaneous optimisation – improving the payback period of a zinc-copper open cut project, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 137–144 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By A K. Ghosh

"Inrush of water is always an issue, especially for mines located in heavy rainfall areas. Nowadays, mining companies and research institutes have developed many advanced technologies for study and analysis of hydrological processes. In this paper, an advanced method is introduced, which uses the Shuttle Radar Topography Mission Digital Elevation Model (SRTM DEM) data in the Geographical Information System (GIS) platform to simulate the stream distributions around two specific mines: Super Pit and Griffin coalmine in Western Australia. The impact of this approach is important because it reduces the time and economic cost by creating a high spatial resolution hydrological map in the specific areas. The study identifies the flow path of the run-off water, which helps in adopting a suitable water management plan surrounding the case study mines. The results match with the ground reality. Based on the results, the stream structure around Griffin coalmine is more complicated than that of Super Pit. The bifurcation ratio and drainage density are computed to estimate the subsoil permeability characteristics of the two mines. Recommendations have been put forward to prevent and reduce the potential risks of water accumulation around the open pit mines.Citation:Ghosh, A K, 2016. Application of Shuttle Radar Topography Mission Data in Hydrological Analyses of Super Pit and Griffin Coal Mine, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 162–169 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By C Smith, J Cilliers, K Hadler

Unstable flotation froths, that burst before they overflow, produce no concentrate. Increasing the froth stability to improve recovery is therefore an obvious control strategy. Froth stability can be measured readily as the fraction of air entering the flotation cell that overflows as froth, rather than bursting on the surface; the ‘air recovery.’ Air rate is one of the most significant variables affecting froth stability. It is interesting that froth stability (air recovery) is maximised at a specific air rate, above or below which it decreases. It is important for metallurgists to realise that this maximum froth stability also produces the maximum mineral recovery, without compromising concentrate grade. Flotation cells must be operated at the air rate that produces the highest air recovery. The peak air recovery (PAR) to maximum mineral recovery relationship was first demonstrated by Hadler and Cilliers in 2009. Since then, the relationship between PAR and flotation performance has been widely explored; varying air rate, froth depth and particle size. Industrially, reducing the flotation bank air rate to achieve PAR yielded better mineral recoveries than other down-the-bank air rate profiles. In this paper, we present an overview of these key developments and findings in flotation optimisation based on PAR. Furthermore, using new industrial data, we show that PAR is not just applicable to rougher-scavenger cells, but also to flotation columns. Finally, we consider the future application of such an optimising control concept. CITATION:Smith, C, Hadler, K and Cilliers, J, 2018. Flotation control using froth stability: past, present and future, in Proceedings 14th AusIMM Mill Operators' Conference 2018, pp 441–454 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 29, 2018

By M D. Griffith

Oct 12, 2022

By S G. Li

Mine intelligent ventilation is an important guarantee to realise intelligent mining. It is the integration of the Internet of Things, big data, artificial intelligence, internet, cloud computing with ventilation technology, forming a complete ventilation system with intelligent perception, intelligent decisionmaking, intelligent emergency response and airflow control. In order to fully grasp the progress and trends of mine intelligent ventilation research in western China. The paper based on literature analysis and field application research, comprehensively expounds the main research and practical results of mine intelligent ventilation in western China, mainly analyses the development status of key technologies such as accurate and rapid determination of mine ventilation parameters, intelligent analysis and decision-making of ventilation and intelligent regulation of ventilation equipment, and introduces the field test or application of mine intelligent ventilation technology in western China. It lays the foundation reference for related research and improving the intelligent level of mine ventilation.

Oct 12, 2022

By S J. Kim, S W. Kim, L Tomas da Rocha, S Jung

Al2O3 has been regarded as a harmful gangue component in iron ore, especially causing reduction degradation in industrial sintering of iron ore. The current study aimed to utilise low-grade iron ore containing high Al2O3 content in sintering process. In order to counteract the adverse effect of Al2O3 on reduction behaviour of iron ore sinter, mill-scale and calcined dolomite were chosen as FeO- and MgO-bearing materials. Firstly, mill-scale was added to high Al2O3 sinter and addition was optimised as 10 wt per cent, then calcined dolomite was added further. Magnetite and magnesio-ferrite were identified as the major phases in iron ore sinter when adding mill-scale and calcined dolomite. As the dosage of calcined dolomite increased beyond 4 wt per cent of in sinter mix, unreacted MgO particles were observed, which is ascribed to the limitation of MgO dissolution into magnetite matrix. Both mill-scale and calcined dolomite were effective in improving compressive load and Reduction Disintegration Index (RDI) of iron ore sinter although its reduction degree was highly decreased. The addition of both FeO and MgO-bearing materials to high Al2O3 sinter has a potential to improve the sinter quality, also contribute to the recycling of industrial by-product. However, the amount should be optimised in views of phase development and deterioration of reducibility.

Jun 19, 2024

Sishen uses a state-of-the-art tracking system to track material from its position in blast blocks through various stockpiles and crushers. Qualities are blended directly to the crusher as opposed to blending from stockpiles. This poses an interesting challenge to the planning department to simulate these conditions. The software used in these simulations are Whittle 4X and Maximiser for long-term planning, Xpac for medium-term planning and Mine Works Planner for short-term planning. Geological models and mine design layouts utilise Surpac. Sishen introduced Xpac a number of years ago; the system has developed and changed over the years. With the Sishen Expansion Project (SEP), which aims to utilise low-grade material, major changes to the planning process have to occur. SEP requires that the mine have two different plants, which utilise two different ROM feeds and have different beneficiation curves. Xpac is used to produce a rolling 18-month plan, which is as close to actual operations as possible. In order to do this, the simulations have to take into account the plants beneficiation curves, stockpile movements, hauling distance and equipment needs. On top of this, the schedule has to continually consider specifications for Fe and the contaminants. Plant yields also have to be kept within a certain bandwidth. Xpac is used to simulate the above parameters, as well as generate the raw data required to produce a mine budget. The paper will also show how the 18-month planning process and subsequent planning processes are measured and aligned. Xpac has proved to be an excellent tool to achieve these goals.

Jan 1, 2005