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By J G Reid

In the period since 1989 the Yabulu Nickel Refinery of Queensland Nickel has undergone a transformation both in terms of the nickel laterite ore feed and the refined nickel product. These two changes were mutually supporting, as will be shown in the following paper. It had been realised since the early-1980s that the Greenvale orebody would be exhausted by 1992. Consequently planning had been in progress throughout the 1980s for the importation of overseas ore as a replacement for the Greenvale ore. The existence of extensive lateritic ore deposits in New Caledonia and Indonesia made these locations the natural focus of attention. With the three Japanese ferronickel smelters sourcing their nickel garnierite ore feed from these locations it was relatively easy for the miners to supply the overlying limonite ore to Yabulu. This limonite ore was previously discarded as waste. The Yabulu refinery now receives about 85 per cent of its ore from these two overseas sources. The transition from Greenvale ore to imported ore occurred gradually between 1989 and 1993. It was during the ore importation planning stage of the mid 1980s that Queensland Nickel commenced the technical investigation which led to the ammoniacal solvent extraction (ASX) plant installation and the product change from nickel oxide to nickel metal.

Jan 1, 1994

By Johnston R. F

The factors which influence the reduction of chromite are investigated with special reference to Coobina chromite. This was compared with a South African chromite ore. The reduction characteristics are outlined and the reduction kinetics studied Temperature has the most significant effect, followed by particle size, silica addition and type of coal.Electron microprobe analysis of the products indicates that iron in the chromite is first reduced at temperatures above 1100°C, followed by chromium at around 1200°C. At temperatures greater than 1200°C metallic iron and chromium are formed simultaneously and subsequently give an iron-chromium-carbon alloy. It was observed that the metallic carbide contains a small amount of silicon. The decomposition of the chromite spinel was observed to pass through the FeO.Cr2O3, MgO.Cr2O3 and MgO.AI2O3 forms before slag formation. It is concluded that Coobina chromite is suitable for the production of ferrochrome if direct prereduction followed by intensive bath smelting is used.

Jan 1, 1994

By Zenari L, Kent D

As our mines introduce more sophisticated production technology into their operations, the dependence on communication systems is markedly increased to allow the management of the technology. However the attention given to the communication systems has lagged that given the production equipment - namely LHDs, trucks and jumbos. At times it was treated as after thought. However, this is changing as the degree of automation increases in our mines. The communication system is now being given much more priority and is genuinely becoming a part of the mine design. The transfer of information around underground, as well as between the surface and underground, is an essential day-to-day activity, with the aim being a smoothly run operation. However the mine environment is far from static, and situations arise - such as breakdowns or other incidents - that require swift analysis of the issue, its cause and its remedy. Also, as communication systems become more sophisticated their use in areas, other than direct data flow, become available. The importance of communication, its development, and new areas being impacted by communication is the subject of this Paper.

Jan 1, 1997

By Ross R

Although mining is an old industry its management is quite a new science, and its complications are now being recognised as demanding expert knowledge in many branches of technical and professional education. Not the least amongst these isaccountancy, for probably its most important problem is "How to control the expenditure." Unlike most businesses a mining company stands almost entirely in the light of a purchaser in the world's markets, and not as a seller, except say for product so the established and perfected systems of modern industries cannot be adopted for mining purposes. For this reason it has been left for late years to consider the matter seriously, and now a number of well-managed concerns have devised costs systems to suit their own requirements.Very little, however, has been published and even that is disjoined and difficult to make use of. Some of the costs systems in vogue, although elaborate and imposing, are not of very great value for keeping check on wasteful expenditure, or for displaying the commercial effect brought about 'by any particular change in practice, or by an addition or alteration to a portion of existing plant.

Jan 1, 1911

By Fitzgerald DE, Taverner MG

The principles, fields of application and equipment design concepts of several new approaches to continuous vacuum treatments of molten metals and alloys are discussed. Partic- ular attention is paid to the results of pilot plant tests evaluating a launder-in-tube method of 1. continuous production of refined zinc from a zinc-bearing lead produced in the lead splash condenser of the Imperial Smelting Furnace (ISF), and 2. continuous refining of crude cadmium. The former trials were not sufficiently encouraging to justify consideration of the process for commercial development. The applic- ation to cadmium upgrading gave very promising results; metal of 99.99 per cent purity was produced continuously at pilot scale (120 lb per hour) from crude metal containing 5.0 per cent Pb.

Jan 1, 1972

Among the various methods of thick-seam mining already well-tried in practice longwall caving with extraction of a single slice, as thick as possible, abandoning the top and/or the bottom coal, seems to be the most suitable one for the Australian coal mining industry. The production units of the future should be equipped with heavy double-drum shearer-loaders, wide armoured conveyors, (with one or two central chains) and shield support. Material of this type has been developed for seams up to 6 m thick. Output figures of more than 6,000 tROM/d from a single face can be looked upon as a quite realistic expectation. The problems of co-ordinating such large production units with the whole layout of the mine are discussed. The factors to be taken into account in the planning work and for preven- tion of mine fires caused by spon- taneous combustion are dealt with. For economic reasons the highest possible utilization factor of the very expensive equipment must be aimed at. Furthermore, the seams or parts of seams to be extracted should be carefully selected.

Jan 1, 1976

By M Akhtar, E Jak, M Shevchenko

This article presents an overview of the experimental phase equilibria studies of S-containing systems (Ni-Sn-S, Cu-Sb-S, and Cu-Sn-S) and As-containing systems (Fe-Sb-As and Fe-Sn-As). These systems improve the prediction capabilities of FactSage in a 20-component ‘Cu2O’-PbO-ZnOFeO- Fe2O3-CaO-SiO2-S-(Al2O3-MgO-CrO-Cr2O3-Na2O)-(As, Sn, Sb, Bi, Ag, Au, Ni, Co) system for complex pyrometallurgical operations during both refining and recycling. Experiments involved equilibration at predetermined temperatures (300–1200°C) with or without preheating, followed by rapid quenching in a brine. Quenched samples were then directly measured using an electron probe microanalyser. For the Ni-Sn-S system, liquid phases (NiS- and SnS-rich mattes and liquid metal) and solid phases (Ni1+xSn, SnS, Ni3Sn, FCC-Ni, Ni1-xS, NiS2, Ni3Sn4, SnS2, Sn2S3 and β-Ni3S2) were observed. A new Ni3Sn2S2 phase was found to melt incongruently. For the Cu-Sb-S system, liquid metal, matte, FCC-Cu, digenite, Sb, CuSbS2, Cu3SbS3 and Cu3SbS4 phases were observed. For the Cu-Sn-S system, liquid metal, matte, digenite, SnS and Cu3Sn phases were found at liquidus.

Jun 17, 2024

Spatial data processing using geographic information systems produces qualitative results which are superior to those from other existing software tools. However, the answers to various quantitative questions in mining operations is often limited by the capacity of the GIS to process appropriate spatial data. The efficient operation of a large underground mine demands that an adequate GIS be put in place.

Jan 1, 1995

By Waters JC

Pseudoclastic hydrothermal alteration textures occur within quenched coherent dykes forming part of a subaqueous dome complex (-4 Ma) on Ponza Island, Italy. These textures are similar to those observed in considerably older (-500 Ma) subaqueous volcanic rocks at a number of localities throughout the Mount Read Volcanics in Tasmania and elsewhere in ancient volcanic sequences of this type in Australia. This is significant because the processes of formation, hydrothermal alteration and secondary mineralisation of ancient volcanic sequences may be better understood if we can make comparisons with modern analogues. Observations at Ponza imply that these pseudoclastic alteration features form synvolcanically or immediately after dyke emplacement and lava extrusion. This is compatible with scenarios presented for their formation in ancient sequences in the Mount Read Volcanics, Tasmania.

Jan 1, 1995

By Albano C, Antila A, Flykt B

A method for relating operating variables and dewatering parameters of Thunes disc filters in the LKAB pelletizing plant at Malmberget in Sweden, via empirical mathematical models is described. Near orthogonal experimental design was used, where all independentvariables were allowed to span over their domain of variation and pseudo-randomly distributed among the experiments. The dewatering parameters are dependent on many variables and instead of using a traditional mechanistic model, an empirical model based on multivariate data analysis was chosen. The way of expressing the relation is by regression coefficients obtained from partial least square regression (PLS). Two empirical models were generated. The models were validated using an extra set of 56 experiments. The dewatering parameters were related to the design variables with few experiments, and user-friendly response surface methodology was used to determine the optimal conditions.

Jan 1, 1989

By Y Gu

Based on the mode of occurrence, gold is classified into three categories: microscopic gold, submicroscopic gold and surface-bound gold. Microscopic gold, or visible gold, refers to gold minerals in which Au occurs in a substantial amount, such as native gold and electrum. Submicroscopic gold, ie invisible gold, refers to gold contained in the structure of other minerals (mainly sulfides) in minor to trace amounts. Surface gold is the gold that was adsorbed onto the surface of other minerals during mineralisation and subsequent oxidation or metallurgical processing. Gold mineralogy has a significant impact on its extractive metallurgy. Gold process mineralogy helps address problems related to gold ore processing. It is widely used as a predictive and troubleshooting tool in gold ore processing, and provides useful information on process selection, flow sheet development, recovery improvement and reagent consumption optimisation. This paper will begin with the classification of gold ores, and will focus on gold mineralogy and how it impacts extractive metallurgy through case studies.

Jan 1, 2008

By Hall T. P, Taylor R. N

Fluid flow in a 1:14 scale water model of the shaft and settler of the Kalgoorlie Nickel flash smelter has been investigated by flow visualisation and numerical modelling. Detailed flow fields through the reaction shaft, settling chamber and uptake are presented for flow rates up to 800 Vm and a number of burner configurations. The predicted flow fields were compared with experimental data obtained from streak photographs and video recordings. The effects of cessation of flow through individual burners and changes in shaft dimensions were also Investigated.

Jan 1, 1992

A case study of a landslide, which threatened vital infrastructure essential for the continuous operation of the Ok Tedi copper mine is presented. The paper presents a detailed description of the land- slide, outlines the assets at risk, and how the issue was addressed. This included the consideration of remedial options and the im- plementation of the most economically sound and geotechnically feasible remedial design which was completed within budget and on schedule. The paper is intended to highlight the responsibility of a mine based Geotechnical Engineering section in providing essential geotechnical investigations, design and professional advice on addressing stability issues in the infrastructure region.

Jan 1, 1997

By Beattie MJV

Widely diverse mechanisms exist for the action of a range of selective sulphide flotation depressants. Collector desorp- tion, leaching, competitive adsorption, formation of hydrophilic reaction-product coatings, action as reducing agents, and action as lattice-oxidizing agents are discussed. Detailed attention is focused on the latter two mechanisms. Recent works on copper depressants particularly for copper-molybdenum separations, and oxidizing agents enabling arsenopyrite- pyrite separations, are presented and discussed.

Jan 1, 1984

Copper heap leaching involves both the simultaneous and sequential leaching of very large tonnages of ore over long periods of time. It is not unusual to be leaching three or four million tonnes over periods of 12 to 18 months. As a consequenc

Jan 1, 1998

By P A. Montoya

La Colosa is a world-class porphyry Au project located in Colombia, currently undergoing prefeasibility analysis. As part of collaboration between AngloGold Ashanti and the AMIRA P843A GeMIII Project, the application of emerging geometallurgical characterisation testing and modelling tools has been incorporated in early stages of project development. The aim of the geometallurgical study is to map inherent comminution variability across the La Colosa deposit providing information critical for mine/mill design and optimisation. In this study, site-based data incorporating multi-element assays, quantitative analyse X-ray difraction QXRD bulk mineralogy measurements, EQUOtip rebound hardness data, and routine geological logging information from 59 diamond drill holes has been integrated with a range of geometallurgically specific comminution test (ie GeMCi, A × b, BMWi). The work in this paper demonstrates the integration techniques used at La Colosa to link routine data acquisition methods with comminution test results through the development of proxy support models. The integration incorporates a range of statistical techniques including principal component analysis and regression modelling. By creating proxy models, comminution index estimates can be propagated into the geological database enabling comminution processing domains to be defined. These domains provide the first spatial representation of comminution performance and variability at La Colosa and can be compared against traditional geological domains. This study provides the foundation for ongoing comminution characterisation as the La Colosa project evolves through project cycles into an operational mine.

Sep 5, 2011

By Staunton W. P

The presence of cyanide soluble copper in gold ores can give rise to serious operational and economical difficulties in CIP and CIL operations. Cyanide consumption can result in the ore being uneconomic to treat by conventional means. Loading of copper onto carbon can also have deleterious effects on gold recovery and subsequent stripping and bullion recovery. The recovery of gold from high copper ores has been previously reviewed by Muir, LaBrooy and Cao (1989). Work undertaken for Mt Gibson Gold Project by Australian Mining Advisors with the assistance of the Chemistry Centre (WA) resulted in the patenting of a process and subsequent construction of a plant at Mt Gibson to overcome some of the difficulties encountered with copper. This paper discusses some of the work which was undertaken during laboratory investigations prior to commissioning of the plant and some further considerations for the treatment of high copper gold ores.

Jan 1, 1991

By Nelson G

The construction and placement of tunnels by means of jacking is continually advancing. This paper presents an outline of the construction of a major highway tunnel placed by a combination of mining and progressive placement by hydraulic jacking of precast units. Features of the project were the relatively shallow ground cover between rail and road routes over the tunnelling and jacking operations and also the weight of tunnel sections to be moved into position.

Jan 1, 1993

By R H. Boffey

The Osborne copper-gold deposit was discovered in North-West Queensland in 1989. Underground production activities commenced at Osborne deposit in April 1996. This paper will examine technical and operational aspects of the underground mine during its development to a 1.2 Mtpa operation . Technical aspects discussed include geology, mine design and mining methods, equipment fleet selection and capital infrastructure. Operational aspects discussed include the evolution and performance of the integrated work teams that are utilised at Osborne to perform all mining and maintenance activities.

Jan 1, 1998

Over the 20 years to 1990 the Australian mining industry, presently worth some $A60 billion, generated a negative real rate of return (McDonald, 1992); not surprisingly under-performing the returns from bonds and industrial equities. Over this same period more than $A70 billion was invested in expanding the Australian mineral industry.

Jan 1, 1993