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By D Bradshaw, J R. R de Villiers

The non-stoichiometric sulfide mineral pyrrhotite (Fe(1-x)S), common to many nickel and platinum group element (PGE) ore deposits, occurs in varying crystallographic forms with the different types exhibiting subtly different physical and chemical properties. These differing properties are likely to influence the flotation performance of pyrrhotite, which in the case of PGE operations is actively recovered, whereas in nickel operations pyrrhotite is depressed. In this study, examination of natural pyrrhotite samples from Southern African and Canadian nickel and PGE ore deposits revealed a variety of pyrrhotite compositions in terms of iron content (Fe7S8, Fe9S10, Fe11S12) and solid solution nickel concentration. Pyrrhotite composition was correlated with its mineral association depending on whether non-magnetic pyrrhotite occurred in conjunction with troilite, non-magnetic pyrrhotite occurred as single phase pyrrhotite, magnetic pyrrhotite occurred as single phase pyrrhotite or whether the two phases; magnetic and non-magnetic pyrrhotite co-exist. Subsequent microflotation tests of selected single phase pyrrhotite samples revealed that the non-magnetic pyrrhotite is slightly more floatable than magnetic pyrrhotite. Microflotation tests also showed that varying flotation responses occur between differing magnetic pyrrhotite samples. These differences in flotation performance are postulated to be a result of the effects of varying pyrrhotite crystallography, trace metal content and mineral association on pyrrhotite oxidation, formation of surface species and subsequent adsorption with xanthate collector.

Jan 1, 2008

Universities have had a long history in the education of geology graduates, Analysis of this history reveals a record of success, as judged on a world basis. However there have been significant changes in the last 20 years that have impacted on the ability of universities to continue to provide their traditional style of geology education. These changes have increased in the last 10 years. In the teaching side, there has been a change in expectations. Additionally the increasing workload decreases the value of each academic to perform the tasks needed by the new education. In the area of research, the funds provided have continued to decline, in both real and absolute terms, and it is now necessary for universities to seek out funds to pay for their postgraduate research. Additionally, the universities have slipped into the error of what cahn only be termed "academic incest", and research student mobility has decreased to an undesirable level, stifling initiative and new ideas in a number of cases, The only solution is for Government monies to be "directed" - ie that the postgraduate student must leave his or her original university in order to receifve the research stipend/scholarship. On the government front, the government and its agencies have not adequately analysed and recognised the need for the redirection of education and research funds into the needy areas of science and technology, especially those that related to the minerals area.

Jan 1, 1986

Rope guides, consisting of ropes spanning between anchor points at the top and bottom of shafts, have frequently been considered as a viable alternative to fixed guides, comprising buntons and guides. However, their design has generally been based on empirically derived rules, arising from European hoisting practice of 50 to 100 years ago. This paper describes a recent technology development project aimed at defining and quantifying the important forces acting on rope guided conveyances, calculating the resulting displacement of the conveyances and assessing whether the displacements are acceptable or not. The paper describes the derivation of aerodynamic force coefficients based on CFD analyses and other significant forces acting on the conveyance and rope system. The conveyance displacements may be calculated using computer simulation of the mechanical system, or approximately using simplified equations given in the paper. Measurements taken to confirm the suitability of the proposed formulation are described. The combination of displacements and assessment of the rope guide system design are proposed, based on the ratio of design clearances and the predicted displacements.

Jan 1, 2005

By M Pyle, R Ch, G Lane, ramhan

Data is the most valuable commodity in the information age. The use of data enables productivity, opportunity, and safety in various sectors and industries. In the late 1950s, Alan Turing coined the term artificial intelligence (AI) to describe the ability of computing machines to think and behave like humans through simplified reasoning and logic (Turing, 1950). This concept of mimicking human behaviour is the building block of machine learning algorithms used in most AI software. The ‘learning’ aspect in machine learning requires data, that is, information on the environment or the objective, to be modelled or predicted using AI. An AI-enabled system aims to predict the unknown faster and intuitively. Intuition in software algorithms can be described as probabilistic, learned through the data that the AI system is trained on; indeed, the AI software cannot predict the future, but it can provide the likelihood of an event/action occurring, thereby enabling decisions or responses to prevent it or take action. Just as various industries have adopted AI as the tool of choice to seek new opportunities (examples: medical research, self-driving cars, financial modelling), the mining industry, too, has been receptive to embracing AI for problem-solving and maximising the value of its business.

Sep 1, 2024

By P A. Jenkins, I W. O Jones

WMC has mined the Perseverance disseminated orebody exclusively by SLC (sublevel cave) methods. Deteriorating ground conditions in the vicinity of an orebody inflection forced a re-evaluation of future mining at Perseverance and a strategy to drop down below the inflection zone and recommence the cave was implemented. This strategy has led to increased production at higher grades, resulting in lower costs and better mill recoveries. This paper describes the evolution of mine planning, development, support and production strategies through the successful process of implementing the ædrop-downÆ and re-establishing the SLC.

Jan 1, 2000

This paper puts the view that, for one gold deposit in Victoria at least, the Australasian Code for the Reporting of Identified Mineral Resources is severely deficient. The author questions whether or not the Code constrains the proper dissemination of information relevant to resource valuation. The author offers a view about the estimation of inferred resources, and provides data believed pertinent to the proper valuation of Ballarat Goldfields Ltd Ballarat East Project.

Jan 1, 1990

By Drinkwater DJ, Watsford RMS, Johnson NW, Munro PD

This paper describes the use of modelling and simulation techniques in the analysis and optimisation of grinding circuits at the Lead/Zinc Concentrator of Mount Isa Mines Limited.The objectives of the studies were to: -1. improve primary grinding circuit performance by reducing the production of -0.006 mm galena fines.2. maximise the fineness of grind in the second existing grinding power and pumping capacitie The study has shown that quantitative models can operations. The models described plant operation,,and simulated the effect of process changes on plant performanc The use of automated scanning electron microscope technology tcliberation characteristics of the major minerals in the Mount isa Lead/Li ore is also described.

Jan 1, 1985

By M A. Harrington-Baker, J M. Trudnowski

Sulfate-reducing bacteria (SRB) have the ability to immobilise dissolved metals by precipitating them as sulfides, provided that a favourable biochemical environment is created. Such an environment includes the presence of sulfate, anaerobic conditions and the availability of organic carbon. If such conditions are engineered within a reactive barrier or field-bioreactor, most metals can be effectively removed. To demonstrate this concept, three passive SRB field-bioreactors were constructed in 1998 at an abandoned mine site in the vicinity of Butte, Montana, USA to treat acid mine drainage with characteristic elevated concentration of metals and low pH. Performance of the field-bioreactors, using aqueous samples, was monitored over 32 months until the project was terminated, field-bioreactors were decommissioned and solid matrix sampling of the reactive matter was performed. The most important analytical results are presented in this paper together with conclusions regarding the appropriateness of the field-bioreactors construction features. Only Zn, Cu, and Cd were being removed as sulfides due to SRB activities. Changes in concentrations of other metals (Fe, Mn, Al, As), which do not necessarily precipitate as sulfide, seemed to be affected by SRB only in an indirect manner by responding to increased pH caused by SRB activity. An innovative cellular containment system used for placing organic matter worked very well in preventing settling of the organic matter and ensuring uniform flow of AMD throughout the entire cross-section of the organic carbon with no preferential flow paths This demonstration was funded by the US EPA and was jointly administered by the EPA and the US DOE under DOE contract number DE-AC22-96EW96405. The project was implemented by MSE Technology Applications, Inc, Butte, Montana, USA.

Jan 1, 2003

By Pratt V

The economic, social and political environment of the mining and minerals industries is, as we all know, volatile and affected by constantly changing international forces. In addition, the outcome of negotiations with overseas customers is often uncertain for long periods, or even unfavourable. The industries and companies represented at this Conference are in an arena of high competition, risk taking and enormous capital outlay. They are industries which our overseas markets (rightly or wrongly) have criticised for industrial relations problems, unreliable production and uncertain deliveries. They are industries which have an urgent need to be cost effective and competitive at all levels of activity.A critical factor in the mining and metallurgy industries is, therefore, its human resources and its human resource management. It requires the full use of available talent, innovation, skills and qualifications within its workforce, and the appropriate management of these resources.

Jan 1, 1985

By T C. Westerfield, G, M J. Mankosa

An innovative separator known as the HydroFloat cell has been developed specifically for the upgrading of coarse particles that are difficult to recover using conventional flotation cells. The novel characteristic of this separator is the formation of a hindered teeter-bed of fluidised solids into which small air bubbles are injected. The air bubbles selectively attach to hydrophobic particles and form particle/bubble agglomerates that segregate atop the teeter-bed due to their lower apparent specific gravity. The low-density agglomerates are eventually carried into the product overflow launder by the rising current of teeter water. Hydrophilic particles remain in the teeter-bed and are discharged to underflow as a high solids content tailing. Benefits of this hybrid flotation-density separator include enhanced bubble-particle contacting, increased particle residence time, and very low air demand. Test data indicate that significant improvements in the recovery of coarse particles can be achieved using this innovative technology. This article describes the theoretical basis for the development of the HydroFloat cell and provides an overview of recent pilot-scale tests conducted for the phosphate industry.

Jan 1, 2005

By Kelly D, Moore C

The Golden Mile, which has been mined continuously for the past 100 years by both underground and more recently open pit methods, occupies an area of 1.2 km by 4 km adjacent to the city of Kalgoorlie Boulder in Western Australia (Figure 1). Large-scale open pit mining at the Kalgoorlie Consolidated Gold Mines (KCGM) Fimiston operations is currently extracting 7.8 million tonnes of oxide and sulphide ore for a total production of 522 000 oz per annum. The effectiveness of grade estimation techniques at KCGM has been examined with reference to existing 10 m bench sample data from all operating areas within the Eastern Lode System of the Main and North pits. The aim of the study was to recommend practical parameters for grade control estimation. The review included comprehensive variography and comparison of nonparametric estimation methods (Joumel, 1983) such as indicator kriging and probability kriging with ordinary kriging, leading to the development of improved grade control parameters and procedures for both daily quality control and short term mine planning. This paper reviews the geological, statistical, geostatistical, mining and modelling features studied in order to present KCGM's Mining Department with recommendations for improving grade control.

Jan 1, 1994

Two significant TBM boreability predic- tion models are outlined. Predicted advance rates are compared with actual advance rates taken from twenty case histories. The results show that a simple low cost method that uses one machine parameter and one rock parameter compares very favourably with a high cost sophisticated method which also includes information regarding discontinuities in the rock mass. The effect of rock texture on drillability is also examined. A method of quantifying rock texture has been developed and is outlined. Experimental results show that the developed TEXTURE COEFFICIENT returns highly statisti- cally significant correlations with drilla- bility data in a wide range of rock types.

Jan 1, 1987

By B C Tanda, E A. Oraby, J J. Eksteen

"Base metal and precious metal deposits are well known for their significant geometallurgical variation throughout the volume of the proven resource. At the metallurgical level, the plant normally processes an upper oxidised layer, a transition zone and a sulfide zone, often leading to different processing techniques for the different zones. A novel processing approach is presented whereby alkaline leaching with glycine is used to leach base and precious metals, using a copper-gold ore deposit as a case study. Glycine is a cheap, non-toxic, non-volatile, highly water-soluble crystalline solid produced industrially in bulk quantities. As a chelating ligand it forms a number of stable glycinate complexes with Ni, Co, Cu, platinum group metals (PGMs), Au, Ag, Zn, Pb, Hg and Cd, with broad stability regions over an extended temperature-pH-Eh range, allowing dissolution of these metals in the neutral and alkaline regions (pH 7–13). It has been shown that this lixiviant system can leach the metals from their oxide, oxy-halide, basic sulfate, carbonate, native and various sulfide forms, including refractory sulfides such as chalcopyrite. Extraction of the metals from their soluble glycinates is easily achieved using a range of solvent extraction and precipitation processes, and the glycine remains stable in aqueous solution for recycle and reuse. Minerals bearing metals in Groups 1 to 8 of the periodic table are normally unaltered. This technology therefore provides a highly selective leaching environment for the extraction of numerous scarce metals of economic interest, with minimal interaction with gangue minerals, whilst using environmentally benign reagents. Problematic leach residues such as jarosites, elemental sulfur and silica gels are averted through this processing approach. This technology allows hydrometallurgical processing that is much less domain-sensitive in the geometallurgical sense, and utilises essentially the same key reagents for the whole deposit.CITATION:Eksteen, J J, Oraby, E A and Tanda, B C, 2016. Developing Robust Hydrometallurgical Processes to Recover Metals from Deposits with Large Geometallurgical Variation, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 15–20 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

By Dutton D

In the British coal mining industry, during the last decade, a great deal of environmental monitoring experience was acquired, particularly in the Doncaster Area of the Yorkshire coal- field, which had a long history of spontaneous combustion and gas emission problems. This paper summarises the experience obtained and shows how the introduction and operation of these systems has resulted in improved techniqu- es for fire detection and control. Some of these systems are described in detail with emphasis placed on the uses to which output data are put, and their impact upon management at colliery level. Reference is also made to the problems encountered in the development of such systems and how they were solved. The paper also makes reference to the recent Research and Development work of the NCB's Scientific Department and Mining Res- earch Development Establishment (MRDE), which was directed to the design and application of a range of underground sensors, and so ensured continuing progress in this field. The paper refers briefly to a new comprehensive monitoring unit and an integrated fire detection and data transmitting system which are currently being assessed in the Yorkshire coalfield.

Jan 1, 1983

By R Castroviejo, E Pirard, L PTrez-Barnuevo

Process mineralogy provides the mineralogical information required by geometallurgists to address the inherent variation of geological data. The successful beneficiation of ores mostly depends on the ability of mineral processing to be efficiently adapted to the ore characteristics, liberation being one of the most relevant mineralogical parameters. The liberation characteristics of ores are intimately related to mineral texture. Therefore, the characterisation of liberation necessarily requires the identification and quantification of those textural features with a major bearing on mineral liberation. From this point of view, grain size, bonding between mineral grains and intergrowth types are considered the most influential textural attributes. While the quantification of grain size is a usual output of automated current technologies, information about grain boundaries and intergrowth types is usually descriptive and difficult to quantify to be included in the geometallurgical model.Aiming at the systematic and quantitative analysis of the intergrowth type within mineral particles, a new methodology based on digital image analysis has been developed. In this work, the ability of this methodology to achieve a more complete characterisation of liberation is explored by the analysis of chalcopyrite in the rougher concentrate of the Kansanshi copper-gold mine (Zambia). Results obtained show that the method provides valuable textural information to achieve a better understanding of mineral behaviour during concentration processes. The potential of this method is enhanced by the fact that it provides data unavailable using current technologies. This opens up new perspectives to the quantitative analysis of mineral processing performance based on textural attributes.CITATION:PTrez-Barnuevo, L, Castroviejo, R and Pirard, E, 2013. New perspectives on quantitative textural analysis, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 191-198 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

A major tool in the search for petroleum is reflection seismic mapping. The period which has seen most of the exploration in Victoria is also one which has seen major advances in this technology, from 1963 try present day. Seismic mapping can be divided into three interlinked areas - acquisition, processing, and interpretation. In acquisition the major changes have been from an explosive energy source in 1963 to gas exploders in 1968 and airguns in 1970. The number of recording channels has increased from 24 to 192, with digital recording introduced in 1966, and floating point recording in 1976.

Jan 1, 1982

By E Kabwe, E Chanda, M Karakus, S Akdag

The Convergence Confinement Method (CCM) is one of the frequently used methods that considers the ground response to the advancing tunnel face. The CCM analytical solutions represent stress relaxation on circular tunnel walls in a rock/soil media. The CCM analytical solutions is based on circular tunnel geometry and consider a hydrostatic stress field in a homogeneous isotropic rock mass condition. However, noncircular tunnel geometries, non-hydrostatic stress field, staged excavation process in a discontinuous anisotropic non-linear rock mass conditions are usually ignored in these analytical solutions. In this paper, we investigate the performance of the existing CCM analytical solutions developed for elastic and elastoplastic ground behaviour for circular tunnels. For this purpose, a finite difference analysis is conducted to compare the analytical results with the results obtained from Finite Difference Method (FDM) for a chosen rock mass condition. Results obtained from the investigation shows that floor, crown and wall displacement are 30%, 10% and 23% more, respectively, in a horse-shoe relative to a circular tunnel. This indicates that the application of analytical formulation tailored for circular tunnels would lead to inaccurate quantification of wall convergence in horseshoe-shaped tunnels. CITATION:Kabwe, E, Karakus, M, Chanda, E and Akdag, S, 2018. Investigating the tunnel closure using convergence confinement method and 2D plane strain finite difference analysis, in Proceedings The Fourth Australasian Ground Control in Mining Conference (AusRock), pp 152–159 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 30, 2018

Production implications of the introduct- ion of electric L.H.D. units in sublevel open stoping and pillar recovery at Rosebery are covered by Faulkner (1982) and Carlton (1982). The following engineering aspects associated with the decision to introduce electric L.H.D.'s are considered here: - Initial requirements for commissioning, including power reticulation at an adequate level to all operating areas. - Conversion of a manual system to radio remote control. - Maintenance backup requirement to ensure that the production potential is realised.

Jan 1, 1982

By M Hedley

Tracking plant and personnel in mining operations provides multiple potential benefits for a mine including improved safety, better monitoring of production, traffic control and, in the future, monitoring and control of autonomous vehicles. The main techniques currently proposed and used for wireless tracking are radio frequency identification (RFID), signal strength based techniques and time of arrival (TOA) based techniques. RFID provide poor accuracy in the complex radio propagation environment present in mines and does not provide continuous tracking and signal strength techniques. TOA based techniques are potentially the most accurate, however, most current equipment has not realised the potential of the technique. CSIRO has been developing the Wireless Ad hoc System for Positioning (WASP) system for wireless tracking in a range of challenging environments including underground mines and surface operations, where GPS reception is compromised by depth. The system utilises a number of ‘anchor nodes’ that are placed at fixed and known locations within the mine and tags attached to the plant or personnel to be tracked. The system provides an ad hoc data communication network, thus, wired data connections are not required to the anchor nodes. WASP uses transmissions in the 5.8 GHz ISM (instrumentation, scientific and medical) frequency spectrum to perform highly accurate ranging between nodes, hence tracking of tags. The localisation performance of the system depends upon the radio propagation environment, ranging down to 0.1 m in low multipath conditions. In this paper we describe the WASP system and provide results of testing in underground and surface operations showing the system achieving high ranging, hence localisation, accuracy.

Nov 22, 2011

By T Baumgartl, M Edraki, L Huang, D R. Mulligan

"Phytostabilisation with tolerant plant species has been advocated as a cost-effective solution for sustainable cover of tailings from metal mines and bauxite refinery. The development of sustainable plant ecosystems on such wastes requires not only tolerant plant species compatible with local climatic conditions, but also the formation of stable and functional root zones through systematic processes to develop functional soil matrix and horizons (eg A-B-C). However, the process requirements for reconstructing functional root zones in tailings are poorly understood. Based on a review of current literature and industry experience in tailings revegetation, the present paper conceptualises three key phases in the process of root zone development in amended tailings: hydro-geochemical stabilisation resulting from the interactions among tailings characteristics, amendment measures and local climatic conditions the rehabilitation of soil biological capacity the establishment of ecological (carbon and nutrient) linkages between the rehabilitated root zones and the above ground plant communities.Key research is required on: the relationship between hydro-geochemical stability and mineralogy and geochemistry of tailings, in response to rehabilitation treatments under local climatic conditions the relationship between soil biological capacity and hydro-geochemical stability in the root zone the transition of soil microbial communities specific to exogenous organic matters into those required for mineralising litters of in situ plant communities.CITATION:Huang, L, Baumgartl, T, Edraki, M and Mulligan, D R, 2012. Sustainable phytostabilisation of mine tailings - A critical analysis of system requirements and approaches, in Proceedings Life-of-Mine 2012, pp 105-116 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 10, 2012