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In order to understand the technique, basic theoretical principles of radiation emission and in- strumentation theory are reviewed. Methods of surveying, reduction of data and interpretation are outlined. Other applications of the technique (e.g. in airborne geological mapping), as well as its specific use in uranium exploration, are discussed. By means of case history-type examples the successful applicant of gamma-ray spectrometry, as a tool in Australian mineral search, is demonstrated.

Jan 1, 1969

The An Shan iron ore deposit is the biggest low-grade oxidised iron deposit in China. Over the past ten years, about 120 SLon verticalring-pulsating high gradient magnetic separators units have been installed in An Shan to process oxidised iron ore. This paper describes how several plants have upgraded their old technologies to new technologies with SLon magnetic separators as the key equipment for controlling tails grades, including using reverse flotation as the key technology for iron concentrate cleaning, These plants have been modernised with beneficial results at low cost.

Jan 1, 2009

By S E. Wallah, D Hardjito, B V. Ran

The manufacture of Ordinary Portland Cement (OPC) is not only energy-intensive but also releases a significant volume of carbon dioxide (CO2) to the atmosphere. In addition, OPC in concrete often causes premature deterioration that affects the durability of concrete structures. This paper explores an alternative to OPC concrete called geopolymer concrete.The present research utilises low calcium (class F) fly ash as the source material to produce geopolymer concrete. Several factors that affect the mix design process such as mix proportion, curing time, and curing temperature have been studied. In addition, the long-term properties such as drying shrinkage, creep, and exposure to sulfate attack are also being investigated.The test data presented in this paper reveal that geopolymer concrete possesses high compressive strength, undergoes very little drying shrinkage and moderately low creep, and shows excellent resistance to sulfate attack. The result is extremely promising and demonstrates the sustainability of geopolymer concrete as a construction material for a sustainable future.

Jan 1, 2004

By M Ranjan, C R. Borra, P Palai, P P. Sahoo

Change in mould slag composition during casting of medium alloy steel is caused by the redox reaction between molten steel and mould flux. Mould flux generally contains a certain amount of SiO2, but elements such as Al, Mn and Ti in high/medium alloy steels reduce SiO2 in the mould flux, causing remarkable changes in the composition of the mould slag. As a result, the properties of the mould slag change greatly as continuous casting proceeds. This causes casting instability, process abnormality and casting defects. Effect of Ti as an alloying element in steel on mould slag is studied extensively through high temperature laboratory measurements and plant measurements. TiO2 gets picked up by the mould slag up to 3 per cent during casting a steel grade containing 0.1 per cent Ti. This changes the mould slag composition and results in decreasing the slag viscosity by up to 10 per cent and decreases slag break temperature by 30–40°C.

Aug 21, 2024

By G Gilchrist, S C. Dominy, T Jashashvili, R C. A Minnitt

The grouping and segregation error is one of Gy’s seven errors that cannot be measured in any qualitative manner because of its transient and changing characteristics each time the sample is handled mechanically. Attempts to calculate the mean and variance of the segregation error is considered by some as ‘an exercise in futility’ that would not help us achieve representative sampling. This research is aimed at understanding the process of segregation of dense, finely divided and dilute particulate materials supported in a clean quartz substrate during intense agitation. Several mixtures of fine-grained materials including steel, tungsten carbide and gold grains were used in these experiments. Four hundred grains of each of the minerals and metals at a top size of 2 mm were mixed with approximately 600 g of finely ground quartz material (95 per cent passing 2000 microns) in a 500 ml plastic jar with a sealable lid. The mineral–?metal mixtures were analysed in three steps using microfocus X-ray computed tomography. Step one consisted of rolling the containers on a flat surface in an attempt to concentrate the mineral and metal grains in the core of the supporting substrate; this is a base case that can be reconstructed after each session of analysis. The second step involved gentle and vigorous shaking of the mixtures in order to segregate the denser minerals and metals from the supporting quartz substrate. In some cases, a third step involved splitting the sample through a riffle splitter. Three-?dimensional images of the surface of each grain, its volume and its X-, Y- and Z-coordinates, before and after intense agitation of the container, were interpreted from the reconstruction of the tomographic X-ray data. The spatial analysis of grains using cell declustering and 3D variography provided a useful means of characterising the distribution of the grains in space and the extent to which they had become segregated during the process of agitation. Spatial analysis indicates that in general, grouping and continuity of grains is weakly developed. The modelled nugget effect remains high for most tests, indicating that grains of similar size did not group together strongly. Agitation through rolling provided the best continuity, although not consistently in the long axis of the plastic jar. The nugget effect was consistently highest, and the range of continuity shortest in samples that had been split, indicating that the grouping and continuity were reduced through splitting the sample. Initial results indicate that very little segregation of the minerals and metals occurs in the quartz substrate. This is somewhat counter-intuitive, but suggests that the effects of agitation on mixtures of dense minerals and metals in substrates of lower density do not lead to excessive segregation. Differences in behaviour between dense materials in response to agitation are evident. Grains of different composition and shape did not group and segregate in a predictable manner in response to the agitation methods. Initial results indicate that the degree to which a material groups and segregates relates more to the characteristics of the denser material itself, rather than the agitation method employed.CITATION:Minnitt, R C A, Jashashvili, T, Gilchrist, G and Dominy, S C, 2017. Quantifying segregation of minerals and metals in particulate materials using computed X-ray tomography and variography, in Proceedings Eighth World Conference on Sampling and Blending , pp 173–182 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By Bawden WF, Paynter JT

This investigation involves laboratory testing and stability analysis of paste fill at the Golden Giant Mine. Site-cast samples are tested in unconfined, confined, and consolidated-undrained triaxial compression. Pore pressures during shear and consolidation characteristics are measured to determine both drained and undrained shear strength parameters and assess the potential for undrained loading. Liquefaction potential is also considered. A limit equilibrium solution is used to obtain factors of safety against failure of the fill during mining of adjacent stopcs

Jan 1, 1998

By C M. Sennitt, M J. Spadafora

Systematic field evaluation of known gold and clay occurrences in South Korea has led to the recognition and discovery of both high and low sulphidation gold-silver epithermal systems. These are associated with Cretaceous acid-intermediate volcanic centres in the southern parts of the peninsula. The high sulphidation deposits such as Seongsan and Kohung are characterised by pervasive silica-alunite-dickite-pyrophyllite alteration with anomalous arsenic geochemical signatures. Gold mineralisation is associated with fine grained marcasite and pyrite. A low sulphidation quartz vein system observed at the Tongyoung mine comprises multistage colloform banded quartz-carbonate assemblages, with minor manganese and base metals. Gold and silver occur as electrum and tellurium minerals. Some deposits such as Gasado and Dogcheon display both high and low sulphidation alteration assemblages. Early pervasive silica-alunite-pyrophyllite alteration caps formed by acid fluids with a significant magmatic component, occur above cryptocrystalline colloform banded vein systems. The quartz vein stage hosts the precious metal mineralisation and appears to have been deposited by later neutral fluids generated in part through mixing with meteroric water.

Jan 1, 1999

By J Durbin

To effectively plan for closure, we must have an end-point in mind. To undertake meaningful rehabilitation, a post-mine land use (or uses) must be known. However, it is becoming more apparent that the end-point or “goal-posts” are shifting - and may continue to do so throughout the life of a mine. As well as being safe, stable and not causing environmental harm, post-mine land uses should always be sustainable, achievable within the given land capability, and they should involve stakeholders in their design and development.The majority of mines in Australia, and around the World, were historically expected to return disturbed land to either native ecosystem or agriculture/forestry practices. However, examples of highly successful final land uses suggest that today’s focus on closure includes not only minimising future liability and impact but also – and importantly – a move towards the creation of economic opportunity (Murphy and Heyes, 2016).CITATION:Durbin, J, 2018. Planning for (not so) final land use, in Proceedings Life-of-Mine 2018, pp 110–112 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By J Pearce, B Miles, V de San Miguel

Incorporating industry best practice waste rock management methods can be a relatively straight forward task when preparing management documentation, such as an acid and metalliferous drainage management plan (AMDMP). However, a key difficulty is the incorporation of industry best practice methods that are practical and non-compromising on their purpose from a scientific standpoint. The second key difficulty is the implementation of these practical methods as various operational groups/departments are typically relied upon to execute and take ownership of different tasks or procedures.One approach to overcoming these difficulties is to develop an AMD Operations Manual (AMDOM) that:•Incorporates, where practicable and without compromising scientific merit, existing processes that those groups/departments ultimately responsible for the execution of the management action are familiar with; and•Provides standalone, simplistic, and easy to follow procedures for site personnel. The purpose of the standalone operations manual is to ensure site personnel who are responsible for undertaking specific procedures, have clear, step-by-step instructions for an individual procedure, without requiring interpretation and understanding of the more comprehensive AMDMP.In adopting a best practice approach to waste rock management for their iron ore mine in Western Australia’s Pilbara region, Roy Hill developed an AMD Management System that is comprised of both an AMDMP and an AMDOM that are connected through adaptive management processes. The Roy Hill iron ore mine, which has a mine life of 18 years, will require the management of more than three billion tonnes of waste rock.CITATION:de San Miguel, V, Miles, B and Pearce, J, 2018. Practical waste rock management at the Roy Hill iron ore mine, Western Australia, in Proceedings Life-of-Mine 2018, pp 80–82 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

The approach to this subject is a very general one, but an attempt has been made to cover briefly a very wide field in the nationally important job of manufacturing iron for the iron and steel industry.Some historical data concerning the development of the furnace itself from early days have been followed by the modern ideas on raw materials and their beneficiation. Recent furnace design and modern auxiliaries have been given attention with, finally, some developments in practical operation.HISTORICALWhen dealing with such large 'and costly operating units as blast furnaces, there is not the same opportunity for research in design as in most other metallurgical processes. Over past generations the development of furnace design, or "lines" as it is usually termed, as well as most radical operating changes, has been very gradual.However, there have been some periods of rapid progress due to revolutionary changes. One such was the adoption of the steam engine for blowing and charging operations, and also, during this same era, about 1750, coke was first used as fuel in place of charcoal. Another revolutionary change came some 100 years later, when heating the blast became usual practice.Since then there have been great improvements in mechanical equipment and in the preparation of raw .materials. These factors, together with a better understanding of what happens inside the furnace, have led to the development of those large mechanically operated structures which are the most modern in blast furnace design.For many, years America has led the world in pig iron production and in furnace development, so that American design and practice is now recognised almost as standard. This type of furnace replaced the older stacks in England, Russia, Germany, South Africa and India, as well as here in Australia.

Jan 1, 1947

By B Yeganeh, A Sam, A Kohsari

The base of separation at Gol-e-Gohar iron ore plant (Sirjan in the south of Iran) is magnetic separation after milling. Magnetic separation in the plant is divided into two parts: dry magnetic separation and wet magnetic separation. Sixty-five per cent of the plant production belongs to the dry magnetic separator section. Therefore, investigation of this part of the plant is necessary. Prediction of plant production is one of the most important subjects in mineral processing plants. That means, before feed enters the plant, specification of production has been calculated with laboratory methods. The purpose of this paper is the prediction concentrate quality has achieved from the dry magnetic separator. The content of iron in the final dry concentrate will be predicted, with laboratory, pilot and modelling methods, before feed enters the plant. Different variables are used in this approach, which consist of: speed of the first dry magnetic separator (rougher), speed of the third dry magnetic separator (cleaner), iron content in plant feed, size of 80 per cent passing of feed, size of 20 per cent passing of feed and iron content in pilot dry magnetic separation concentrate that performs in a standard manner. The artificial neural network is used for modelling and one of its branches is the radial basis network (RBN). Iron content in magnetic separating concentrate in plant will be introduced as the target and will be calculated with the RBN method. In the RBN method, a set of data enters to neural network and they will be trained and simulated. Finally, the target will be predicted. Ultimately, the original target (actual iron content) and the predicted target (predicted iron content) compare and error of them will be calculated. The obtained result is acceptable and satisfactory.

Jan 1, 2007

By McCarthy P. L

A distinctive feature of the goldfields of Victoria was the extrac- tion of gold from deep leads, that is the buried river beds of Vic- toria's ancient rivers and streams. It is estimated that about 265,000 kg of gold was produced from Victoria's deep lead mines which comprises about 11.5% of Victoria's total production of gold (Bowen, 1974). The significance of deep lead mining for Victoria, however, went far beyond its economic contribution to Victoria. If Profes- sor Blainey is correct it was the frustrations of mining gold from deep alluvial leads in Ballarat during 1854 which precipitated the Eureka Stockade (Blainey, 1963, 46-52). This event resulted in the implementation of a fair mining administration and was an emphatic statement of the rise of democratic movements in Australia. Much of the technology and skill for mining deep leads had to be developed locally because at that time no other major gold- field elsewhere in Australia or the world had gold deposits with comparable problems. Deep lead mining in Victoria was there- fore largely a home grown industry and the equipment for that industry was often designed and produced in Victoria.

Jan 1, 1988

By J Cronin

For the last decade, we have read about the great technical innovation that is coming to the mining industry that will increase safety and productivity. There is consensus that it will be a technical innovation that will produce a step change in mining costs and outputs (as opposed to bigger machines or less people); however, this innovation (while freely available) has not taken hold in the industry. While there are a few mines that have embraced technology, the majority of underground mines simply do not have the expertise or technical capability to implement innovation and automation.With unexploited mineral deposits becoming deeper and more remote, and thus more hazardous to mine, telepresence offers the ability to remotely execute production tasks while separating personnel from hazards. As the technologies required to deliver telepresence mature, the potential for there to be no personnel underground during production activities is becoming a reality (the ‘dark factory’). So significant is the capacity of telepresence to mitigate risk, it is proposed that it be included as a separate entry in the hierarchy of hazard mitigation controls.Technical innovation such as the optimised short-term interval control of the production process and the automation of underground mobile fleets offer significant increases in production along with lower operating costs. This paper explores the most critical components for the successful implementation of technology in underground mining; redundant, robust and high-bandwidth communications networks to carry data from distributed networks of smart sensors and to convey teleoperation commands; and high-definition video to provide operators with detailed, real-time data. The days of analogue ‘leaky feeder’ as a base case for communications are over. The human resources required to support the expected wave of innovation are significant and will be difficult to maintain in remote areas as the same skills and expertise are in demand in other industries.The paper highlights barriers to innovation in the mining industry, and a lack of technical and scientific expertise within the industry to be able to identify, implement and manage technologies that can increase safety and productivity. As well, an over-reliance on basic net present value (NPV) financial analysis that is used in the industry punishes investment in technology (capital expenditure; CAPEX) and accepts higher operating expenditure (OPEX) due to the discounting of future savings in operating costs.CITATION:Cronin, J, 2017. Telepresence – the application of remote control and automation technologies for increased safety and productivity, in Proceedings 13th AusIMM Underground Operators’ Conference 2017, pp 213–224 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Oct 16, 2017

By A Markham

Stream diversions are a common feature of mine sites worldwide. From an operational perspective, a fundamental requirement of a stream diversion is that it should convey water flows between two points in a safe, controlled and predictable manner. On the other hand, rivers and waterways are naturally dynamic systems, and many of their natural values are achieved through their ability to alter their forms and processes over time in response to flow events - often in a potentially unsafe, uncontrolled and unpredictable manner. In order to ensure that diverted river reaches achieve the dual objectives of short-term operational stability and longer term physical equilibrium with surrounding landscapes, alteration of form and process must somehow be understood and incorporated into the design process. However, performance targets for waterways are not always easy to define and assessing what is good and bad in such variable systems can be difficult. This paper discusses the role of the stream diversion from the operational, environmental and regulatory/relinquishment perspectives, and how stream diversions must achieve physical stability in the short-term, but dynamic equilibrium in the long-term.CITATION:Markham, A, 2012. Mine site stream diversions - A balance of competing objectives, in Proceedings Life-of-Mine 2012 , pp 215-218 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

The problems associated with achieving adequate accuracy for on-site axial flow fan performance measurements are discussed. The ability to test accurately rests heavily on equipment and installation design detail.Aerodynamic performance trials frequently cannot be carried out due mainly to the poor standard of installation design. In a majority of cases this results in unsteady, non-uniform inlet flow conditions to the fan. Details of installation design features and instrumentation, necessary for successful testing, are given for different types of installations and methods of testing. These cover both conventional practice, and new innovations which can provide solutions to difficult problems. Quantitative aspects of flow measurement are considered for various fan and duct configurations.Although the main emphasis is on large primary mine ventilation units which require on-site testing, the principles outlined have wide application to many other types of fan installation.

Jan 1, 1973

By P Navarra, R Kuhne

Dynamic simulation (discrete event simulation) is the preferred methodology to evaluate the impact of dynamic aspects of processing plants on the overall plant capacity. This tool can be used to: identify bottlenecks in the plant,justify upgrade and expansion projects by evaluating their impact, oroptimise maintenance and operating practices without disrupting the operation. Iron Ore Company of Canada's (IOC) pelletising plant is a complex operation because of multiple products, varying equipment capacity and shifting bottlenecks. Furthermore, with extensive capital requirements for projects and long lead times, a high level of confidence in project outcome is required. Therefore, a model of IOC's pelletising plant in Labrador City was constructed in 2007 by a joint IOC and Hatch team. The model includes both operational and metallurgical aspects in order to better capture the complexity of IOC operation. In this paper, the justification, boundaries, and functionality of the model are described. A comparison of simulation results to historical plant operation is given. It is observed that projects have interactions and that the benefits of combined projects are not equal to the combined benefits of the individual projects. Projects can have synergies that result in greater benefits when combined or can have overlapping benefits that result in lower benefits when combined. The power of the proposed modeling exercise lies in the ability to assess the impact of projects on overall performance.

Jan 1, 2009

By R L. Verburg, R Johnstone

DeBeers Canada Mining Inc (DeBeers) recently submitted an Environmental Assessment (EA) for its proposed Snap Lake Diamond Mine located in Northwest Territories, Canada. As part of the EA process, a site water quality management plan must be developed. Plan development requires an integrated approach such that the key factors influencing water quality can be identified and managed to minimise potential impact. A system model was therefore developed to simulate the site-wide water quality conditions and mass loadings to the principal environmental receptor of concern, Snap Lake, during operations and post-closure. Requirements of the simulation included integrating hydrology, geochemistry, hydrogeology and site management practices in a dynamic way. A unique feature of the site was the need to accommodate a complex flow system that included a feedback loop between lake water and mine water. A system model was constructed using the GoldSim software package that integrated on-site water quality and flow measurements, as well as results from independent groundwater flow and geochemical modelling efforts. The GoldSim model simulated concurrently the movement of 39 solutes through the subsurface mine and surface facilities. Solute sources considered included four different waste rock and tailings types, explosives use in the mine, treatment plant discharge, and recycled process water for dust suppression. Separate solubility constraints were identified for different regions of the flow system (eg underground mine; treatment facility; surface water bodies). Kinetic test data were used to derive temperature-dependent rate constants for use in calculating mass inputs from surface sources such as waste rock piles. The model generated water quality estimates over time for a variety of management scenarios at several potential discharge locations. The integrated approach used by the model was effective in identifying the significance of key factors influencing overall water quality such as explosives use, mine water inflow rates, waste rock reaction rates, site/mine management options, and effectiveness of treatment. The model provides an example of an effective tool for comprehensive, integrated system evaluation and management.

Jan 1, 2003

By J Joy, A Bye, G V. Kizil

This paper presents an application of the newly developed risk-cost-benefit (RCB) framework to support risk management decisions for the selection of wall monitoring technologies at an open cut mine site. The RCB framework quantitatively assessed the risk of unstable slope-induced wall failure and its impact on both loss of life and coal recovery. The RCB framework was utilised in the selection of an optimum group of risk-controls to effectively manage the risk of wall failure to ensure safety and optimal production occurred. The RCB framework incorporates mathematical modules that integrated RCB calculations and risk-control effectiveness assessments to determine the risk reduction and financial impact of the examined safety initiatives.This paper provides an overview of the five-staged RCB framework, incorporating the RCB decision support tools, RCBGEN (Risk-Cost-Benefit Generator) and RCEMETHOD (Risk-Control Effectiveness Method), and demonstrates its application to slope stability risk management at the case study site. The RCB charts are designed to display a balance between risk, cost and benefit for easy interpretation by decision makers to support the objective selection of an optimum suite of risk-controls. The RCB analysis revealed that a combination of ævisual inspections, automatic extensometers and radarÆ for fast- and slow-wall failures with structure were sufficient to reduce the probability of loss of life (PLoL) to the æModerateÆ zone as defined by the Australian Geomechanics Society (AGS, 2007) for the case study site. The new framework presented in this paper provides a method to effectively determine the suitability of risk-controls and supports industry efforts to reduce risk to as low as reasonably practicable (ALARP).CITATION:Kizil, G V, Bye, A and Joy, J, 2012. Risk-cost-benefit analysis of early warning technologies impact for wall failure risk management in surface mines, in Proceedings Eighth Open Pit OperatorsÆ Conference , pp 55-64 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 18, 2012

By J Taylor, M Smith, A Tunnadine, D Nikolakopoulos

As Olympic Dam rapidly expands into the Southern Mine Area (SMA) the Mine Geology team has concurrently ramped up underground diamond drilling to sustain rates of above 175 km/a. With >10 underground rigs double-shifting, traditional paper sections used for the management of drill programs were no longer optimal due to scale of operations. An opportunity was identified to modernise monitoring of all underground diamond drill programs, through the integration of logged copper sulfide estimates with Olympic Dam’s first-fully integrated deposit-scale geological model in Leapfrog Geo. This paper describes the transition within the Mine Geology team from reliance on 2D paper sections, towards near-real time 3D geological modelling for optimising end-of-hole decisions in the field. This transition was enabled by innovative database solutions informing locally constrained implicit models, limited by a distance buffer around active underground fan drilling. Due to the high volume of historic drilling, there were significant computational challenges with the implementation of daily production style implicit models at Olympic Dam and initial testing of regular updates to implicit gradeshells and sulfide domains required in excess of 12 hrs to run. The enabling solution was to optimise the interfaces between the AcQuire database, Deswik MDM and Leapfrog Geo to create a dynamic, streamlined workflow that was easily completed by Mine Geologists in accordance with daily production duties. Geologists are now building rapid implicit models for a range of variables from an integrated data set of logged sulfide estimates and existing assays, spatially constrained by 150 m buffers around active drilling using a unique drill fan identifier flagged during the planning phase. Once the live-implicit models are updated, they are exported for visualisation on field tablets to be used during logging and core checks at the start and end of every shift. To manage the risk of ‘going digital’ interpretation remains at the forefront of the drill section close-out process, with Mine Geologists critically reviewing the finished sections on a standardised template with new learnings wireframed and communicated to stakeholders. The Live Field Model has enabled a step-change in the geological effectiveness of diamond drilling, reducing over – and under-drilling ore-waste at Olympic Dam continuing to push drilling effectiveness towards 20 per cent of intercepts >2 per cent Cu. In addition, upside or risk identified during the proactive management of drilling execution can be rapidly capitalised or mitigated.

Mar 22, 2022

By X L. Liu, W Huang, J M. Zhu, S L. Wu

The shape, position and thickness of the cohesive zone have a great influence on the operational performance of the blast furnace. Many researchers have found that the high temperature properties of iron ores determine the formation of the cohesive zone. The results of this work show that sinter of high basicity interacts with lump ores and acid pellets due to the difference in chemical compositions. The softening and melting properties and the primary slag formation behaviours in the cohesive zone are improved by the high temperature interactions. The high temperature interaction is mainly influenced by the chemical compositions, porosity, interfaces and so on. Although the softening and melting properties and primary slag formation behaviours of lump ore A (a typical limonite lump ore from Australia) is the poorest of the iron ores studied, the high temperature properties of integrated burden A (consisting of sinter and lump ore A) is no worse than the other integrated burdens due to the high interaction between the sinter and lump ore A. It is useful to apply the results in the optimisation of blast furnace burden.CITATION:Liu, X L, Wu, S L, Huang, W and Zhu, J M, 2015. High temperature interactivity of iron ores in the cohesive zone of the blast furnace, in Proceedings Iron Ore 2015, pp 363–366 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015