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By R Piper

The Yabulu Nickel Refinery commissioned in 1974, processes lateritic ore via a modified Caron process to produce high quality nickel and cobalt products. The Greenvale orebody provided the sole source of feed to the plant until 1990 and with well-blended mineralogy, it resulted in stable and predictable plant performance, allowing the operating focus to be on reducing energy consumption and increasing ore throughput. This approach provided better economics than pursuing increased reduction efficiency. From 1990, increasing quantities of lateritic ore were imported from Indonesia, Philippines and New Caledonia. This introduced considerable variation in ore blends and instability in plant operation but also provided the opportunity to treat higher grade ore blends which yielded higher reduction efficiencies. Ore reduction is conducted using 12 Herreshoff multiple hearth reduction furnaces, using heavy fuel oil as reductant. The æROASTERÆ Project was approved in November 2000 with the primary objective of improving Nickel reduction efficiency by: Stabilising Roaster Operation via a structured program including focused maintenance efforts, capital equipment upgrades, new process measurements, process re-design and improvements to operating skills and process troubleshooting. A structured technical program including laboratory and plant studies using one plant furnace as a pilot unit to develop improved knowledge of how the reduction process proceeds in the Herreshoff furnace. Armed with this knowledge, optimised process conditions and a reduction process model were developed contributing to a significant demonstrated reduction efficiency improvement. Technical input to the project was provided by QNI with Hatch providing the engineering and project management for the $8.5 M capital work. Execution of the work included extensive consultation with the plant operators and close cooperation between the Hatch project team and QNI operations personnel ensuring installations were completed with minimal production disruption. A strong focus on safety management resulted in a number of brownfields project relevant safety initiatives being implemented resulting in project completion without a serious injury.

Jan 1, 2002

The results of the washing of coal are often presented by using Partition Curves. By analogy, it is possible to express the results of screening by using similar partition curves. As in the coal washing processes, this method determines the accuracy of screening and is also suitable for different separations depending on the difference in size distribu- tion. This method compares the effectiveness of two screening operations and forecasts the performances.

Jan 1, 1984

Much of New Zealand is comparatively young geologically in the sense that it has only recently been uplifted. In many places young marine sediments are to be found at high altitudes, as evidenced by the existence in the North Island of Pliocene shell limestones which form prominent escarpments at altitudes of about 3000 ft. inthe central part of the Island, and remnants of the same formation found on the summits of the northern Ruahin.e Range at altitudes greater than 4000 ft.

Jan 1, 1962

Platinum Group metals have been known in New Zealand since the 1880's but not produced on a large scale. They have been neglected because their value was not appreciated rela- tive to gold and their value was often very low, reflecting demand, and because recovery was difficult compared with recovery of gold. With the rising price of most Platinum Group metals and the perfection of gravity and flota- tion recovery methods, recovery of platinum along with gold from alluvial deposits is more attractive. Platinum Group metals are known in several different environments in New Zealand, ranging from alluvial placer deposits to layered basic to ultrabasic intrusions and quartz veins. None of the known occurrences have been ade- quately prospected and there is a real possibi- lity of future discovery of important deposits. Several New Zealand based and at least two offshore resource companies are currently involved in exploration, prospecting or mining for Platinum Group metals in New Zealand.

Jan 1, 1987

By Goldstone A

The paper introduces a newly developed multi-function test rig for fracture grouting. This test rig has many functions and its performance is consistent. It can control and adjust accurately the opening degree of fissures and static pres- sure; it can measure automatically the quantity of grout injected; it can measure precisely pressure drop of grout in fissures; it can test the results of injection, including effective dispersed distance, anti-filtration capacity of consolidated body, mechanical strength, etc. It can inject a single or two grouts into one or several fissures at a pressure of 16 MPa. Therefore, it is an ideal test rig for fracture injection. The paper depicts all the components of the test rig, its performance and application of the results obtained from fracture grouting tests. Examples are briefly described.

Jan 1, 1988

By N J. Beukes, J Gutzmer, C Reinke, M Bau

In this study the light sparse phase search (SPL_Lt) mode on the Mineral Liberation Analyser (MLA) was successfully used to identify and quantify the abundance of rare earth element (REE) phosphates in Precambrian iron formations. Monazite (light REE phosphate) and xenotime (Y and heavy REE phosphate) are identified and data from the MLA combined with the mineral chemistry of the two minerals are used to calculate and model the expected REE concentration and distribution in these two REE phosphates. The REE phosphates account for up to 31 per cent of the REEs in the banded iron formations (BIFs) and excellent correspondence is observed between the modelled REE patterns and the whole rock geochemical data available for the same samples. Except for quantifying the mineral weights, the sparse phase search also allows for the localisation of REE phosphate grains and the observation of their association with other minerals using backscatter electron (BSE) imaging. These observations are used to conclude that the REE phosphates were most likely of diagenetic origin, with REEs and phosphate remobilised from primary chemical precipitates. It is demonstrated that automated mineralogical techniques can be used to qualitatively and quantitatively describe the influence of a rockÆs trace mineralogy on its geochemistry.

Jan 1, 2008

Wire rope, when used for hoisting on a mine is the weak- est and most vulnerable unit in the most expensive'-group of installations or! the mine. With the introduction' of hoisting on the S1Koepe"' sheave, a new technique was-established. This innovation brought with it the certain- advantages which long had been recognised and which are being developed further. For many years, drum winders of many types had been the sole means by which ore had been hauled from mines. This type of winder, with its capacity for rope storage on the drum, permitted mine operating personnel to cut short lengths from

Jan 1, 1964

By F Pothitos, S Hewson

The geological and geotechnical conditions at the Cadia Hill Open Pit are very complex. This complexity coupled with high mining rates has required significant technical input into the design and optimisations of the pit slopes, accesses, cutbacks and scheduling. A multi-discipline team of NML engineers, geologists and external consultants has been conducting comprehensive geological and geotechnical programs in order to achieve an optimum design of the pit slopes. Extensive data collection, analysis and interpretation has led to the formation of working geotechnical models of large structures, rock masses, and back-analysed slope performance charts. The current Cadia Pit Optimisation Project focuses on the risk-and-return principle for pit design and on the integration of geotechnical, hydrogeological, mining engineering and scheduling. The risk management for pit design has also been incorporated into the short term and long-term operation of the pit mining to ensure safety and production.

Jan 1, 2003

By Leigh J. H

A history is given of the dust control techniques developed and applied by the mining companies at Broken Hill. A history of the regeneration works undertaken since 1936 is out- lined. Particular emphasis is placed on the stabilization of mine residue dumps which are located throughout a belt of mining leases in the middle of the city and which began in 1937. The establishment of vegetation for dust control techniques is discussed in detail and a case study is given of the successful revegetation of the sides of a 650 metre long, 350 metre wide and 35 metre high residue dump.

Jan 1, 1976

The Mineral Research Centre is located at Perth in the suburb of Waterford, adjacent to Curtin University of Technology and within a Technology Precinct which includes Technology Park. The Centre, constructed by the WA Government at a cost of $16 million and occupied in late-1994, comprises three separate buildings housing the CSIRO Division of Minerals, Curtin University's School of Chemical Engineering and the Mineral Processing Laboratory of the Department of Minerals and Energy. The emphasis on R&D at the Centre is primarily in hydrometallurgy as a result of staff expertise, extensive bench and pilot-scale facilities, track record with the industry and, very importantly, two of the occupiers being partners in the AJ Parker Cooperative Research Centre for Hydrometallurgy. Staff in the Centre have a long involvement with R&D agencies such as AMIRA and MERIWA. The hydrometallurgical focus of the Centre complements that of pyrometallurgy at the GK Williams CRC in Melbourne and the Centre for Mining Technology and Equipment in Brisbane, to ensure that the mineral processing industry in Australia has access to a complete range of expertise and facilities to serve its needs.

Jan 1, 1996

It is difficult with inadvertent explosions to establish fundamental data, especially of original dust, of pressure, temperature etc. and of ventilation oscillations, as exposed personnel rarely survive. Retrospective data from explosions must be derived from damage, from fatalities, from ventilation analyses, from analyses of dusts and other indications of temp- erature and duration of temperature. The five disastrous explosions selected for analysis provide examples of what data can be established as to the cause and extent of explosions. Such information is required for legal etc., inquiries subsequent to explosions, but most importantly to give the best guidance for avoidance of possibility of further Disasters.

Jan 1, 1981

Asbestos is a commercial term applied to fibrous varieties of several minerals, the properties of which are not generally appreciated by the majority of geologists. A thorough knowledge of these properties and of the uses of asbestos is of fundamental importance in the assessment of the economic value of an occurrence of asbestos. The varieties of asbestos that are used predominantly by the manufact- urers of asbestos products are chrysotile, crocidolite and amosite but chrysotile constitutes 95% of the world's usage. It is the properties of high tensile strength, 'heat resistance and large surface area that make chrysotile asbestos the most acceptable of the mineral fibres. There are no known exploration aids, other than direct visual inspec- tion of outcrops in ultrabasic environments, that could be used in the exploration of chrysotile asbestos. The surface exploration of an occurrence of chrysotile asbestos is relatively routine, though it lends itself to a unique form of bulk sampling by the use of a twelve inch diameter diamond drill core. The laboratory assessment of the prop- erties of the actual fibre requires specialized techniques and tests to assess not only the amount of fibre present but also its length distri- bution, inherent strength, filterability, dust content and other prop- erties. The way a fibre reacts to milling will determine what milling process- es must be implemented to ensure a product that is acceptable to the asbestos product manufacturing industry.

Jan 1, 1971

INDEX OF CONTENTSIntroductionChemical compositionsNormally Cooled MattesPort Kembla mattesMount Lyell matteMount Morgan matteGranulated MattesConclusionsIllustrationsINTRODUCTIONIn a previous paper in these Proceedings(l) an account was given of the composition of some copper-lead mattes from the Port Pirie Smelters. The research programme of the Mineragraphic Section of the Commonwealth Scientific and Industrial Research organization has since been extended to copper-iron mattes from Port Kembla (The Electrolytic Refining ana Smelting Co. of Australia), Mount Lyell (The Mount Lyell Mining and Railway Co.) and Mouilt Morgan (Mount Morga:p. Ltd.).Chemical Composition of the Mattes.The mattes examined have a considerable range in chemical composition, as is shown by their analyses (Table 1).

Jan 1, 1949

Incompetent ore and country rock have caused stability problems in longhole open stopes. Fully grouted pre-placed cablebolts have reduced these by preventing ground relax- ation and joint dilation to maintain a self supporting rock structure. Larger atope spans can now be opened with the same or smaller pillar. Mining methods are expected to become less dependent on original ground conditions. Effect of spacing, orientation and stress distribution along the cablebolt is not fully understood at this stage and requires more Observation.

Jan 1, 1977

This paper details a proposal for integrating the use of the Pilbara Iron Ore Classification (PIOC) and stratigraphic data for fine tuning blast. pattern design on Mt Whaleback. The main thrust of the proposal is based on the assertion from Haqan and Harries (1979) that rock properties influence blasting results more than explosive properties. This premise is supported by a literature search, which indicated that blasthole burden, spacing, stemming and subdepth lengths are also determined by rock properties if the same explosive and blasthole diameters are used. A brief explanation of the PIOC is provided during which it is noted that the classification is based on physical hardness, mineralogical and genetic characteristics of the ore. The classification also extends to the two main waste rock types LBIF (banded iron-formation) and shale]. Ore type plans produced from face mapping indicate that many areas on Mt Whaleback can be divided into various PIOC zones and regions thus making it more useful in blast pattern design. Several recommendations for blast pattern design experimentation are made for hard, medium and soft ores as well as for the waste rocks, the most important being the use of expanded patterns to blast. soft BIF and medium hard to soft shales.

Jan 1, 1986

By Weyer J

Many existing computer planning programs for the mining industry focus either on big mining enterprises with a high production rate or on smaller operations for high value minerals. Big mining enterprises, like the hardcoal company `Ruhrkohle AG' in Germany have their own R&D departments which develop powerful computer programs for planning purposes, partly in co-operation with mining universities. However, there is a remarkable number of small- scale mining operations which are either not able to buy expensive hard- and software or don't have the skills for the operation of extensive software programs. Partly there is also a trend in using rule of thumb calculations rather than computer programs which need a lot of - partly unavailable - data. For this reason a computer program was developed which does not need expensive hardware and software and which can help the planning engineer in the selection of a limited number of possibilities. Until this time the planning engineer established two or three different cases and calculated the results with a pocket calculator. This could last some hours or even some days. Now he or she can use the computer program with a normal PC to compare the cases. All activities are menu-driven. The basis for all, calculations are fixed and variable costs as well as average performance for special activities. The paper gives an example for a possible planning situation in fluorspar mining (originally this program was developed for the fluorspar enterprise Lengenfeld in Germany). It shows the initial situation, the main structure of the program, the input logic and the results. Benefits, limits and possible extensions of the program are discussed.

Jan 1, 1995

The disadvantages of the present zinc producing methods, RLE and ISP, are high energy consumption and environmental problems. Therefore, efforts have been directed in Outokumpu Zinc towards the development of alternate routes. One interesting pyrometallurgical process to produce zinc is to inject zinc calcine together with a solid reductant into molten iron, saturated with carbon. This process has been studied by thermodynamic calculations, laboratory tests and mini-pilot test runs at Outokumpu Research Oy, Pori, Finland. The results of these tests are presented and discussed in this paper. The mini-pilot tests demonstrated that over 97 per cent evaporation of the zinc was possible using a reactive coal dust as the reducing agent. The recovery of zinc in the metal phase was at best 88 per cent of input zinc, but only part reported in molten lead in the splash condenser. The final metallic zinc contained at best 98 per cent Zn, the main impurities being dissolved lead and coal carried along with the flue dusts.

Jan 1, 1993

By Hollis R. G, Tuppurainen J. M I

Improved control of non-ferrous sintering operations requires the on-line measurement of sinter quality. No on-line measure of sinter quality is currently available, however, previous work has shown that the raw mix chemistry and peak sintering temperature determine the mineral phases formed and hence the resulting Blast Furnace behaviour. Control of these factors should therefore lead to improved quality control. In this paper, the development of a simplified heat and mass balance model of the Sinter Plant at Mt Isa is described. The model used available plant data to calculate raw mix composition and a simplified reaction scheme to predict sinter composition. The extent of reaction is inferred from the flue gas analyses. Off-line testing of a dynamic version demonstrated that actual plant performance could be predicted with reasonable accuracy.

Jan 1, 1989

By Kyle J. H, Misra V. N

The most recent development in gold processing is the increasing use of heap leaching for the extraction of gold from low grade ore, and old tailings dumps. The reason for this trend is mainly to do with economics. The advantage of heap leaching is the considerable saving in both capital and operating costs. However, not all ores are amenable to heap leaching. It is only applicable to well oxidized ores that have suitable permeability char- acteristics, and the gold recovery is poorer than by conventional process. In this study, an attempt has ben made to ascertain the heap leaching characteristics of Western Australian gold ores on the bench scale using multiple, appropriately sized leach columns. The influence of particle size, flow rate, column depth and leaching time on the rate of gold extraction was determined. The percolation rate of cyanide leaching solution was deter- mined with and without gypsum additions. Efforts were also made to minimise particle segregation, fines migration and solution channelling during leaching, so as to improve solution percolation, gold extraction rate and recovery.

Jan 1, 1991

The, Ore-bodies.-The ore-bodies of the North mine, North Broken Hill Ltd.; consist of two lenses, connected by a narrow neck of mineralized country. They pitch at an angle of 40° in an easterly direction and dip north at 60° to the horizontal. The southern ore-body, on a horizontal plane, has a total maximum length of 800 feet and in one place attains a width of 230 feet, whilst the northern orebody has a maximum'length of 600 feet and a maximum width of 80 feet.

Jan 1, 1940