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By Rowena C. Duckworth

The Ocean Drilling Program (ODP) is the largest international geoscience project in the world, and the state-of-the-art drill ship, the JOIDES Resolution, is permanently at sea. Each year there are six scientific cruises (legs) which each last approximately two months. These legs are designed by geoscientists from the nineteen countries that subscribe to ODP. Australia and Canada presently share ODP membership under the banner of the AUSCAN Consortium. The benefits of Australia's involvement in ODP include internationalisation of Australian geoscience, advanced graduate training, and unique scientific investigations of the ocean floors in the Australasian region. In addition, visits to Australian ports by the ODP drill ship, the JOIDES Resolution, contribute up to $2 million per visit to the local economy. Amongst the many other aspects of ten years of scientific drilling, ODP has significantly contributed to our understanding of hydrothermal processes on the seafloor. To date, three hydrothermal sites have been drilled to date by the ODP, Snakepit (MAR), Middle Valley (Juan de Fuca Ridge) and TAG (MAR). Two more hydrothermal sites are scheduled for 1996.

Jan 1, 1995

By R G. Reddy

The complexity in treating environmentally harmful impurities such as As, Sb, Bi from the base metal matte or metal in the smelting stage are responsible for the high cost of the refining process. The impurity capacities (such as arsenic, antimony and bismuth) of slags were calculated a priori using Reddy-Blander (RB) model. The capacity predictions were for a wide range of matte and slag compositions in copper smelting conditions. The calculated impurities capacities and impurity distribution ratios results are in good agreement with the available experimental and industrial slags data. The a priori knowledge of impurities is useful for reduction of energy consumption and enhanced environmental control in the current and future non-ferrous metal processes.

Aug 21, 2024

By Palmer DJ

Mercury is introduced into EZ's electroly tic zinc/sulphuric acid plant complex at Risdon, Tasmania, in zinc sulphide concentrate. Mercury is volatilised during the roasting operation and then distributed in the sulphuric acid plant effluents and product acid. Following an investigation of the factors determining the mercury distribution, a plan was formulated to-provide an environmentally accep- table degree of mercury containment at Risdon. This paper discusses details of the various control measures investigated and out- lines the reasons for selecting the particular procedures finally adopted for the Risdon plant.

Jan 1, 1980

By D Phillpotts, S M. Mantsho, P Strobos

A challenge on many industrial flotation circuits is controlling concentrate mineral grades using measurements that are provided infrequently. The mineral grades in concentrate streams are a critical performance indicator in any industrial flotation circuit. Failure to achieve concentrate mineral grade targets has significant financial consequences on a flotation operation. A violation of a gangue mineral grade limits by the concentrator may also result in significant penalties. Online grade analysers which can provide reliable real-time grade measurements are essential for effective grade optimisation. The Blue Cube MQi analyser (by Blue Cube Systems) has recently come to prominence for its ability to rapidly determine mineral concentrate grades online and in-stream. This has provided excellent insight into the actual process dynamics in the flotation circuit, and hence enabled real-time control and optimisation of concentrate mineral grades. MintekÆs Measurement and Control division, specialising in advanced control solutions for mineral and metallurgical industries, has had the opportunity to link the FloatStar Grade-Recovery Optimiser to the measurements provided by the Blue Cube system at a nickel concentrator plant. The project initially focused on stabilising the final concentrate grade without directly accounting for nickel recovery. The site later procured additional Blue Cube MQi analysers, resulting in the expansion of the FloatStar Grade-Recovery Optimiser to incorporate recovery component in the performance. This site already had the FloatStar Grade-Recovery Optimiser for several years, but the original grade measurement device was unreliable and ultimately failed. The system was reactivated once the Blue Cube system was installed, replacing the old analyser.CITATION:Mantsho, S M, Phillpotts, D and Strobos, P, 2012. The implementation of FloatStar grade-recovery optimisation control solutions using Blue Cube online grade analysers on industrial flotation circuits, in Proceedings 11th AusIMM Mill OperatorsÆ Conference, pp 363-368 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 29, 2012

By N Maistry, C Carelse, A Singh

Banded Iron Formations or more commonly known as BIF are sedimentary rock formations with alternating silica-rich layers and iron-rich layers that are mainly composed of iron oxides (hematite and magnetite), iron-rich carbonates, and/or iron-rich silicates. Considering the depletion of highgrade iron ore reserves in South Africa, there is a need to maximise resource utilisation through the exploitation of low-grade/uneconomic resources particularly BIF material, which makes up more than 65 per cent of current reserves. Previous test work conducted by alternative BIF sources globally indicates the need for fines processing in order to produce a concentrate. South African BIF however is amenable to coarse and fines processing producing an on-grade product or blended feedstock. C-Type material within South Africa’s Northern Cape Province grading at approximately 33 per cent Fe was supplied for research purposes. Top size optimisation via gravity Heavy Liquid Separation (HLS) tests was conducted. The laboratory results being perfect separation (Ep=0) were modelled to predict pilot performance, the results of which were tested on a pilot scale for the finest size fraction (-1 mm). It was observed that a top size of -2 mm provided optimum results in terms of upgrade and recovery, with crushing finer not necessarily producing superior results. At a target grade of 60 per cent Fe, recoveries of 65.6 per cent were achieved on the laboratory scale, whilst recoveries of approximately 58 per cent were achieved on the pilot scale. Targeting higher upgrades of 63 per cent would inevitably result in lower recoveries of 57.2 per cent on a laboratory scale and approximately 54 per cent on a pilot scale. This is in line with grades and recoveries achieved globally for BIF material albeit at finer grind sizes.

Sep 18, 2023

Continuous, steady-state laboratory flotation tests showed that the recovery of cha1copyrite from a naturally occurring ore, under conditions closely resembling those of plant practice, could be expressed in terms of a first order rate equation.Tests on full-scale plant flotation cells, using impulse tracers, indicated ideal mixing of the pulp in the cells.It was demonstrated that values of first order flotation rate constants can onlv be obtained from conventional methods of analysis in special cases.Analysis of a plant sampling campaign by the author supported a first order kinetic equation for two mineral species, and for the individual size fractions of one of these.The effect of stage-addition of reagents is interpreted in kinetic terms.

Jan 1, 1966

By R Wei, Y Peng

With the depletion of high-quality ores, the efficiency of extracting difficult gold ores through flotation and leaching becomes very important in the mining industry. Iron contaminants, sulfide and carbonaceous coatings on the surface of gold and gold bearing minerals significantly hinder the recovery of gold during gold processing. As the surface of gold minerals is easily contaminated, coatings of iron oxides and iron hydroxides originated from the grinding process and oxidation of iron sulfides will cause a retarding effect on both gold flotation and leaching.To mitigate the processing issues caused by undesirable surface coatings on gold minerals, a new technology in treating surface coatings of iron contaminants has been developed. The pulp potential and pH of the slurry are altered to allow dissolution of surface coatings which are further excluded by the use of complexing reagents. The current work shows that iron contaminants can be removed from the surfaces of gold through Eh-pH adjustment and chelation which result in significantly improved gold flotation response. The addition of complexants aids the formation of iron chelates to prevent the iron species in the solution from forming iron oxide and iron hydroxide in the flotation conditions.CITATION:Wei, R and Peng, Y, 2014. Mitigating the effect of surface coatings on gold processing, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 187–192 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By H Bao, M Nehring, M Kizil, P Knights

The mining sector, a notably energy-intensive industry worldwide, is a major consumer of fossil fuels, leading to significant carbon emissions globally. The move towards electrification, coupled with advancements in battery technology, has redirected focus from traditional diesel-powered solutions to battery-powered alternatives. This paper introduces a novel mining haulage system, termed the Battery Trolley system, and examines its theoretical foundations, configurations, and operational processes. It offers a comprehensive analysis of the system’s characteristics and limitations. Through a hypothetical road simulation, the study analyses various battery mining trucks, calculating energy consumption based on force parameters and tailoring battery sizes to contemporary materials and technology. When assessing various battery truck alternatives—considering aspects such as battery size, effective payload, duty cycle, energy efficiency, productivity, and single-shift production—a range of performance outcomes and characters become apparent within the mining context. The findings indicate that Battery Trolley configurations, requiring smaller battery capacities, entail lesser compromises on effective payload. Consequently, these configurations achieve a higher duty cycle, reduced energy consumption per tonne, heightened productivity, and enhanced singleshift production capabilities compared to Battery-only alternatives. The comparative analysis of Battery Trolley with stationary charging (BT-S) and Battery Trolley – dynamic charging (BT-D) underlines that battery Trolley systems are capable of overcoming the challenges associated with battery size, thus successfully fulfilling the production demands of large truck applications in mining. This positions Battery Trolley systems as a more advantageous option for the decarbonisation of mining fleets, underscoring their potential in contributing to the sector’s sustainable evolution.

Sep 1, 2024

By G Sartor, A Rich, D Grimsey, R Forzatti, M White

An in-depth process model was developed for the pyrometallurgical, off-gas systems and water balance of the Kalgoorlie Nickel Smelter. This model was used to assess plant capacity with changing concentrate grades, increased throughput and tighter environmental emissions under a range of potential future operating conditions. Comparison of modelled results allowed for flow sheet optimisation across a range of metrics including sustainability, processing capacity and costs. Process modelling software, METSIM® (ver 2020.06 by METSIM International), was used to simulate the flash furnace, integrated electric slag cleaning furnace, Pierce-Smith converters, matte granulation, waste heat boiler, hot gas handling equipment, wet gas cleaning plant and acid plant. The METSIM® model was divided into three separate, yet interconnected models: metals, off-gas and water balancing. This allowed for improved modelling efficiency and traceability while minimising manual error. The METSIM® model was supported by inputs from other specialised software. Chemical thermodynamics software, FactSage™ (ver 8.2 by GTT Technologies), was used to establish relationships for the flash furnace fluxing strategy and determine the operating temperature. Arena® (ver 16.0 by Rockwell Automation), a discrete event modelling software, was used to simulate material movements within the aisle as well as Pierce-Smith converter operation, allowing for integration with upstream and downstream systems. A dynamic data exchange (DDE) was used to connect the results of each software package, interfacing through Excel® (version 4203 by Microsoft). The integration between models provided a streamlined approach to test capacity, bottlenecks, water consumption and emissions under a range of operating conditions, enabling a more robust process. Further downstream modelling techniques were used to assess mechanical equipment. METSIM® outputs provided key parameters for combustion assessments using computational fluid dynamics and finite element analysis for the furnace mechanical design.

Aug 21, 2024

By C Itotoh, K O’Halloran, L Karlson

Global methods used to explore for minerals have progressed relatively slowly since the development of the first diamond core drill in 1863. Since then, key developments such as wireline geophysics (1920s), the tricone drill bit (1930s) and aeromagnetic surveys (1940s) all occurred in response to global events. In this project, BHP’s WAIO Geoscience operations team hypothesise that a global movement towards a greener future as well as an increasing intolerance for safety events will drive another step change in exploration methods. We have leveraged our relationships with exploration contractor partners and industry leaders to develop a realistic vision for 2033 and beyond, where drill rigs, earthworks and geophysical units are operated and maintained remotely; emissions of dust and waste are eliminated; hazardous energy sources are controlled; procurement is based on sustainability rather than cost and carbon emissions are tracked with the same rigour as production metrics. We have combined these visions into a series of graphical illustrations with the aim of inspiring ourselves, our vendors and our peers to collaborate further on producing a step change in our industry.

Sep 18, 2023

By G Chitombo

Mass mining methods have become the mining industry’s preferred way of extracting most of the world’s most important metal and mineral commodities. Given the rapidly increasing global demand for commodities, the requirement to increase the contribution of some of these (eg copper and gold) from underground sources also continues to grow. In the case of copper this contribution is needed by a number of major producers to supplement production from their ageing deep open pits. Satisfying this increased demand will require the design, construction and operation of more effective, higher capacity and larger scale mines which, in turn, will require enhanced mass underground mining techniques such as block caving (BC), panel caving (PC) and sublevel caving (SLC).It is now widely accepted that future discoveries of orebodies, which will be developed using these methods, are almost certainly to be much deeper than the deposits presently being mined in this way and made more challenging because of the likelihood that the associated grades may be much lower than currently mined. The design and mining of future large-scale cave mines (supercaves) will become crucial in order to extract full value from such deposits. An essential prerequisite of this will be a much improved knowledge of the deposit, ie Total Deposit Knowledge. In this context, Total Deposit Knowledge is the characterisation of the ore deposit and its surrounds at all scales and includes; rock type (lithology), the spatial orientation of a range of geological features or discontinuities, rock mass fabric knowledge, metal grade and distribution data, geometallurgical data (including alteration), geo-hydrology, permeability and porosity. This is the information that will be used, as now, to delineate geological and geotechnical domains and construct models, but with outcomes superior to those presently available. From this information better-informed feasibility study design decisions and performance predictions must be made. In summary more geological information and analysis is required and this needs to be aligned to potential mining and processing requirements much earlier in the project than commonly occurs.

Aug 22, 2011

Efficient project planning during the detailed feasibility to final engineering stages of a project requires not only the accurate prediction of the grade, tonnes and recovery, but their degree of variability as well. An understanding of the major parameters involved in the grade and tonnage estimates is essential, and the communication to those receiving the results is most important. The personnel involved in the project require more than just a global reserves classification. Quality parameters other than grade should be evaluated as carefully as the estimate itself. This paper does not present any novel ideas to overcome or enhance any of this. Rather, it takes a step back and tries to look at the global picture of requirements for proper project planning.

Jan 1, 1987

By Reichardt Y

Fine feed fractions in the size range from 1 to 40 ¦m of materials with different hardness as limestone and silicon carbide have been stressed in two different devices. A tungsten-carbide-blodc allows a single stressing with a pressure up to 2000 MPa and a 4-piston-block enables a multiple stressing procedure in which the material bed is stressed in alternating directions with a pressure up to 700 MPa. The experiments show energy absorption as the major factor for the interparticle breakage of hard material, like quartz, zircon silicate, silicon carbide and smelted oonindum, pressure, however, does not influence the results within the investigated range from 100 to 700 MPa and even up to 2000 MPa for corundum. But the breakage of the middle-hard limestone depends on the pressure so far as more fineness can be produced if the same energy is introduced at a lower pressure level. The creation of very fine and microfine fragments decreases strongly with increasing hardness of the feed materiaL The energy consumption for producing microfine material with a multiple stressing procedure on a particle bed is much lower than that one of a usual milling process. But this procedure needs a classification with a seperation cut at a couple of microns, which is not easy to accomplish.

Jan 1, 1993

This paper explores the use of a Process Safety Management (PSM) system to manage risk in the mineral processing and metallurgical refining industries. Important elements of a PSM system are described. International regulations and non-regulatory guidelines covering PSM for high hazard industries are reviewed. Case studies of incidents in the mineral processing and metallurgical refining industries are presented to understand the lessons learned from failure to manage risks using a PSM system. Conclusions are drawn to adopt PSM in the minerals and metals processing industry as a tool for loss prevention and risk management.

Jan 1, 2003

By D Chalmers

"There is a tendency to treat mine roadways with fan installations as leak proof systems. Morecomplex ventilation arrangements are being installed in coal mines out of necessity or designand these can introduce additional hazards. This paper explores the leakage paths that can existaround fans and in particular the hazards these leakage paths may generate around undergroundfan installations. The behaviour or these leakage paths in the event of a fan failure has also beenexplored. Early detection of spontaneous combustion is essential, so understanding the leakage behaviour around fans especially boosters or main fans installed underground will assist in sett ing up monitoring locations in the correct places. If this behaviour is not fully understood then monitoring may be placed incorrectly, or trends may not be picked up until it is too late."

Jun 1, 2012

By F R. M Pires, R M. Carvalho

Supergene processes in banded iron formation (BIF) result in important dissolution, material transport and simultaneous disorder of the residual bands. The rock physical properties such as density, porosity and rheology change during the weathering attack. The itabirite, Paleoproterozoic metamorphic BIF from Quadrilßtero Ferrffero (QF) û Brazil, shows several weathered facies. Strong linking between topographic surface, rock density and iron grade occurs within the weathered zones. This linking is due to partial dissolution of silica and carbonate from itabirite and gravitational rotation and break of the remaining blades, generating kink-like slump structures. The original itabirite density, 3.7 t/m3, decrease at the first leaching steps, until 2.7 t/m3, and increase at the end of the leaching process until 3.6 t/m3. Iron grade increases from 38 per cent to 68 per cent and depressions (sinkhole), subsequently filled by Cenozoic basinal sediments, are developed over the enrichment zones. The formation of important supergene iron ore deposits of QF is intimately related to such a process. Several iron deposits at QF, such as Pico do Itabirito, Fßbrica Nova, Casa de Pedra, Tamanduß, -gua Claras, Cappo Xavier, etc., reveal the aspects related to the proposed evolution, implying that the formational process of the soft iron ores had a regional character. Granular medium model helped in the understanding of the development of the structure and the formation of the deposits. A numerical model has been developed in order to simulate a leaching system in a two-dimensional matrix, composed of two types of materials: leachable and unleachable. Equal volume proportion and vertical banding were considered. Drilling data was used as multipoint attractors to remove leachable matrix nodes.

Jan 1, 2002

By S Liu, N M. Rana, A Take, N Ghahramani, D Clohan, S McDougall, S G. Evans, H J. Chen

Tailings dam breaches have caused significant life loss, social, economic and environmental damage in recent years. The term "tailings-flow" refers to various forms of tailings outflow movement resulting from the breach of a tailings dam. These flows, comprising a mixture of tailings, water and dam materials, can take different forms, ranging from a debris flood to a flowslide, and can travel long distances and impact large areas. The inundation extents depend on the failure mechanism, tailings dam height, total released volume, sediment concentration (associated with the rheological behaviour of the flow) and downstream conditions (including topography, land cover and presence of a water body). Numerical runout modelling of tailings dam breaches is important for predicting the dynamics and extent of tailings-flows, which are crucial steps in tailings dam consequence analysis and risk management. This paper presents a comparison of numerical simulations of the 1994 Merriespruit tailings dam breach using three numerical models: DAN3D, FLO-2D and MADflow3D. Using compiled site condition information and data from the literature and public domain, model performance was evaluated primarily based on comparisons between the observed and simulated inundation extents. The main purpose of this preliminary model benchmarking exercise was to help us evaluate the capabilities and limitations of each model, and to identify opportunities for future model improvements as part of a broader research initiative known as CanBreach. This exercise also highlights the inherent complexity of tailings-flows and the importance of using judgement to interpret model input and results.

Jul 1, 2021

By J Lyons, M Hasan, D Pepper, C Vadeikis

Processing of large volumes of ultrafine ores has long challenged mineral processing operators because of lower recoveries and increased tailings. This has led to many deposits, or parts of existing deposits, being viewed as uneconomic. As the mining industry can no longer afford to overlook resources that require finer sizes to achieve liberation or result in high tailings losses, the need for technologies to address these issues has increased. Mineral Technologies (MT) worked with a prominent Australian iron ore producer over five years to implement an innovative gravity separation technology for the beneficiation of ultrafine magnetite. The magnetite mineralisation requires a liberation size of <40 μm and selective rejection of ultrafine silica prior to magnetic separation. Through collaboration with the client, MT applied their Lyons Feed Control Unit (LFCU) technology for the beneficiation of finely grained magnetite. LFCUs are widely used in the mineral sands and iron ore gravity plants, and in tailings applications, to recover water and provide constant high density process streams. This project was an extension of knowledge gained from these applications. Test work was conducted on-site, using 1 t/h pilot and 300 kg/hr laboratory scale units. This test work showed that the LFCUs could reject 20 per cent of feed mass to tails whilst recovering >94 per cent of Fe to product. This upgraded the feed from 53.7 per cent Fe and 19.7 per cent SiO2 to 63.8 per cent Fe and 8.8 per cent SiO2. Recovery by size data showed a minimum 88 per cent Fe recovery to product for <8 μm material and up to 98 per cent Fe recovery for the -38+25 μm fraction. The LFCU rejected 70 per cent of <25 μm SiO2. The information obtained from the test work was utilised in the design of the full-scale units which are due for installation at the project site in 2021. This paper outlines the results of this laboratory and pilot scale test work and how the data obtained was used to design the full-sized units.

Nov 8, 2021

By C Tapia Cortez, A G. Dempster, R Fradet, S Saydam, T de Roche, R Shishko, J Coulton

Human ventures into space are entering a new phase in which missions formerly driven by government agencies are now being replaced by those led by commercial enterprises – in launch, satellite deployment, resupply of the International Space Station and space tourism. In the not-too-distant future, commercial opportunities will also include the mining of asteroids, comets, the Moon and Mars. This research examines the role of off-Earth mining in a growing space economy. In this investigation, the term ‘mining’ is taken to embrace minerals, ice/water and other in situ resources. As the off-Earth mining initiative could be the engine that drives the space economy, it would be useful to understand what off-Earth mining market conditions and technology requirements are needed for that economy to prosper. These specific elements are studied in the wider context of creating an economy that could ultimately support a sustainable Mars colony. The methodology for developing the model focuses on the extraction of ice from the surface of Mars to produce propellant and water for life support for a possible colony.CITATION:Saydam, S, Shishko, R, Tapia Cortez, C, de Roche, T, Fradet, R, Coulton, J and Dempster, A G, 2015. An integrated economics model for in situ resource utilisation in support of a Mars colony, in Proceedings Third International Future Mining Conference, pp 305–312 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By D A. Williams, P J. Chapman

Constructing upstream raises with tailings is an accepted and cost-effective practice in Western Australia, where the climatic conditions are favourable, desiccation (and hence overconsolidation) occurs rapidly due to air drying and there is a perceived low seismic risk. This is in contrast to many other settings, where there is either a positive water balance, high seismicity or a combination of both. In recent times, there has been an increased focus on seismicity in areas of Australia that have historically been considered to be of low seismic risk. The increased focus is driven by two recently published documents used by tailings practitioners and increased awareness from corporate entities, particularly those with mines in high-seismicity regions such as South-East Asia and South America (particularly Chile).The increased awareness has resulted in increased rigour being applied to seismic design of tailings storage facilities (TSFs) in general, and particularly upstream-raised TSFs. This paper compares the results of a seismic stability assessment for an upstream-raised TSF located in the Goldfields region of Western Australia, which has historically been considered a low seismic area, with a seismic stability assessment carried out for a crossvalley TSF containing similar tailings but located in a high-rainfall, high-seismic setting in South-East Asia. The influence of the adopted design earthquake values on the results of the assessments and the potential impact of the maximum design earthquake (MDE) on the design approach is presented for both cases. The results indicate that although the Western Australian site is located in an area thought to have low seismic risk, the screening level analyses suggest that the MDE could result in liquefaction of the tailings materials. Not surprisingly, liquefaction was also indicated for the South-East Asian site. The outcomes of the assessment are also presented.CITATION:Chapman, P J and Williams, D A, 2015. Seismic design of upstream-raised tailings storage facilities in a semi-arid, low-seismicity setting, in Proceedings Tailings and Mine Waste Management for the 21st Century, pp 157–162 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015