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By Tanner A. C, Harraway D. H

Various circuits were tried at Mount Isa Mines during the period 1959 to 19G3 with the objective of improving the differential flotation of galena and sphalerite. Many benefits and disadvantages of the various circuits were revealed. An analysis' of ore characteristics and their effect on flotation was made -and resullted in the design of a proposed circuit which is currently in the process of installation.INTRODUCTIONSince 1936 when lead-zinc sulphide flotation commenced at Mount Isa, at least three types of ore have been encountered.Each ore has presented problems to flotation metallurgists.The three types of ore are,1. partially oxidized upper level sulphide ore,2. Black Star ore from the lower levels with its carbonaceous fraction, and3. Black Rock ore which is similar to 2, but more free milling.In retrospect a number of the metallurgical successes of the past were short lived. Often flowsheets or 0perating practices were designed to solve a single metallurgical problem associated with the current ore being treated. As the ore changed the problem would vanish and the method originally taken to counter the problem could become unnecessary or deleterious to the treatment of the new ore. The general lesson learnt from-the past-is-that thetreatment of Mount Isa lead-zinc ore involves a number of equally major problems...

Jan 1, 1963

By H Zhou, T Honeyands, M Zhou

In iron ore sintering, packing the granules onto the sintering strand to form a porous bed with optimum permeability is a complex dynamic process. The packed bed voidage is the key factor determining the flame front speed and the final sinter productivity and quality. Previous studies have found that granules are soft quasi-particles with a typical structure of nuclei with an adhering fines layer. The deformation of the adhering layer greatly affects the bed voidage during packing, which is related to the strength of the adhering layer and the force exerted on the granules. In this study, tablets simulating the particle size distribution in the adhering layer of granules were made for four single ore blends. Both the tensile strength and shear strength properties of these tablets were investigated as a function of water content by the uniaxial compression test and direct shear test respectively. The results of compression tests show that the adhering layer becomes weaker and more compliant with the increase of moisture. The most porous ore has a more rigid adhering layer than the other three tested iron ores at any given moisture content. In direct shear tests, the internal friction angle of the adhering layer ranged from 31° to 37° and varied little with the moisture content or ore type. The cohesion constant is around 1 kPa and is quite small compared to the stress applied to the granules during packing. Combined with the results of granulation and packing experiments, the influence of the adhering fines layer deformation on the degree of voidage loss is specifically discussed.CITATION:Zhou, M, Zhou, H and Honeyands, T, 2017. Tensile strength and shear strength properties of the adhering layer of granules in iron ore sintering, in Proceedings Iron Ore 2017, pp 117–112 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By P R. Denize, V S. Wein

A brief review of the Waipipi Iron Sands Limited company history and operations over the past ten years is made along with a summary of the benefits of this mining company to New Zealand. Land rehabilitation procedures in coastal dune lands are described in detail and brief mention is made of a study of animal health and copper uptake. The paper concludes with a summary of the increased emphasis on agronomy and restoration as the mining operation commences dredging in a better class of grazing land.

Jan 1, 1981

By Woodcock J. T

During the dissolution of gold in fully aerated cyanide solutions the CN ion is the active agent, and consequently the usual method of evaluating the dissolving power of such solutions is to determine the CN- concentration analytically. The presence in the solutions of copper and/or zinc which themselves form complex cyanides, may result in erroneous conclusions as to the free cyanide ion concentration determined by titration.In this paper the theory of titration of such solutions has been developed, and potentiometric methods have been used to follow the behaviour of complex cyanides of copper and zinc. The results for cuprocyanides show Cu (CN)s to be the most important copper complex, and in addition they explain the reported low rates of solution of gold in copperbearing solutions which when titrated in the usual way, appear to have adequate free cyanide. An explanation of the misleading value of the titration is given, and suggestions for recognition of the condition are offered. Preliminary results for zinc-bearing solutions show that there is no satisfactory end-point for the titration of CN- in excess of that in the complex Zn (CN) 4=, which dissociates to CN and Zn(CN)g-.

Jan 1, 1950

By P Williams, S Flynn, R Birchfield, R Simcock, R Toft, P Comeskey

Direct transfer, or community translocation, comprises salvage and replacement of intact æsodsÆ of vegetation together with underlying soil. It has been applied to New Zealand mine sites restoration of native grasslands, wetlands, scrub lands, and forest. It is an equivalent technique to æinstant lawn or tree gardenÆ, commonly used in urban landscaping. Two to six m2 scoops of vegetation, with up to 0.7 m of soil attached, and including root plates of trees and shrubs, are relocated from stripped areas ahead of mining to sites prepared for restoration. Direct transfer uses hydraulic excavators or face shovels and dump trucks, possibly with the aid of bulldozers and other earthmoving machinery. The main advantages of direct transfer, compared with sowing or planting systems for mine site restoration, are the recycling of plant and soil materials which were often wasted by burying under overburden materials, a significantly faster revegetation process, and restoration of the whole ecosystem (plants, animals, birds, invertebrates, and microbes). The main disadvantages are higher costs of stripping and dumping, a greater degree of machine operator skill required, and scheduling becomes critically important. To illustrate the key principles, this paper gives examples of successes and failures of the technique for a variety of New Zealand mining situations. Direct transfer has been successful for a range of communities, from fern wetland and sub-alpine tussock grasslands to 5 m-tall beech forest under storey and seral shrub land, and from temperate to sub-alpine climates. Successful examples show both rapid recovery of indigenous vegetative cover and conservation of habitat for birds and invertebrates. Failures have resulted from excessive death of plants because of inadequate soil salvage depths, acidic leachates, inappropriate handling of stripped sods by inexperienced machinery operators, or prolonged drought conditions immediately following relocation. Change in plant species composition has occurred where clumps of vegetation are too far apart, or shifted plants were too small - in both cases invasive weeds have smothered the original vegetation. Changes in hydrology can also have significant impacts. Our experience indicates that the advantages of direct transfer far outweigh the disadvantages and is now used as the preferred restoration method, where practicable, at mines where it has been trialled.

Jan 1, 2000

The discussion in this paper centres on examples of mining that are drawn mainly from the coal mining industry. The intention is to review the opportunities that exist for incorporating environmental planning into mining industry practice in New Zealand. The coal mining examples serve to make some general points which have some application for many types of mining.

Jan 1, 1981

Currently in Canada there are 15 major mining companies with a minimum of $1 billion in market capitalization or net private value. This group forms the core of an important sector for Canada. The mining sector had gross revenues of about $35 billion in 1988. This compares to a Canadian GDP of $410 billion in 1988. There are at least three different sub-groups within the mining group, each facing the future with very different prospects for the coming years.

Jan 1, 1989

Some low grade South Australian iron ores were classified on the basis of their physical characteristics. Ores from Mount Christie and Billeroo are coarse grained mixed ores; Mount Christie ore could be concentrated by gravity or dry magnetic separation at 10 mesh, but Billeroo ore needed to be crushed minus 36 mesh. Ores from Razorback Ridge and Wilgena Hill are fine grained mixed ores; ore from Wilgena Hill could be concentrated by flotation, but poor results were obtained on Razorback Ridge ore. Malcolm Creek ore is non-magnetic and crystalline, and can be concentrated by flotation, but the deposit is small. Ores from Grants Quarries and Peeralilla Hill are nonmagnetic and earthy and could not be satisfactorily concentrated.INTRODUCTIONThe Geological Survey of South Australia has for several years been undertaking a systematic study of the iron ore resources of the State (excluding the Middleback Ranges) in relation to their geology, reserves, and beneficiation. As part of the latter phase of the investigation samples of the ores have been submitted to The Australian Mineral Development Laboratories (AMDL), and it was the study of these samples which provided the material for this paper.The mineragraphic and metallurgical work was undertaken by several officers of AMDL and the results are contained in unpublished reports submitted to the South Australian Department of Mines. Field data published here was obtained from unpublished reports by G. F. Whitten, Senior Geologist, Iron Exploration, of the Geological Survey of South Australia.

Jan 1, 1964

By J Taylor, L Richards, M McKenzie

When a collapse in its services shaft caused rapid gas build up and its premature closure in. 1951, the Blackwater Mine at Wiauta was in full production with significant ore reserves yet to be mined. A total of nearly 23 tonnes of gold was produced from the mine during its 44 year life. It was New ZealandÆs deepest underground mine, producing gold from an extensive sub-vertical mineralised quartz reef that averaged 0.6 m in width. Mining was by stoping between adits and short shafts, latterly with the main mine access through the 840 m deep Prohibition shaft. Macraes Mining Company Ltd are presently investigating the possibility of reopening the mine. This paper outlines a preliminary assessment of the main geotechnical factors for achieving the reopening, using recent exploration and old mine information. The greywacke host rock mass in the vicinity of the quartz reef has been evaluated using both these sources, and the paper discusses how the geological structure, intact and rock mass strengths, the rock mass defects, in situ stresses, and groundwater inflows may effect the reopening and support of the prohibition shaft, the excavation methods and support for a new supplementary shaft, and the likely excavation and support requirements for working adits and stopes in the rejuvenated mine.

Jan 1, 1996

IN this paper it is proposed to present certain features of operating practice at the Port Pirie works of The Broken Hill Associated Smelters Proprietary Limited, in the smelting in a blast furnace of lead ores carrying a high concentration of zinc.The subject matter selected for presentation is:(i) The effect of zinc on lead blast-furnace operations, together with an outline of the methods adopted in actual practice in dealing with the zinc problem.(2) Development of the height of tuyere above the bottom of the jacket, and the extension of the tapping interval and the combined effect of both factors upon the lead content of blast furnace slag.It will later be seen that one phase of the investigation carried out in connection with the effect of zinc on blast-furnace operations was largely responsible for the decision to increase to a marked degree the height of the tuyere above the bottom of the jacket.Due to this interdependence, it has been considered advisable to deal with the two features above mentioned.The high concentration of zinc in the lead-bearing materials smelted at Port Pirie has brought with it those troubles which are associated with zinc in the smelting operation.In the early stages of the history of The Broken Hill Associated Smelters Pty. Ltd. the trend towards increasing cost for labour, fuel, and stores, etc., rendered it necessary to increase the lead content of the charge, and reduce to a minimum the quantity of barren flux used.

Jan 1, 1931

The mineral composition and microtextures of a cubanite-rich sulphide ore are described and cubanite breakdown textures are illustrated. The occurrence of cubanite in macroscopic dimensions is featured.The origin of the ore is tentatively related to a composite ore fluid arising initially from an ultramalic source and extracting some metal components from an older granite mass along the margin of which the serpentine was emplaced. Some alternative possibilities as to origin are also mentioned.

Jan 1, 1969

By McDonald G. G

In the deformation of a metal or a single-phase alloy all the crystals composing the metal after their shape in a similar manner as the metal in bulk and to about· the same extent. This is not the case in an alloy consisting of two phases of different resistance to plastic deformation. In such an alloy the two phases take part in the deformation approximately in inverse proportion to their hardness, at least at the beginning of the deformation. (1) The hardness difference becomes less in the course of the deformation and thereby the deformation more equal. The phenomena occurring during cold-rolling of some two-phase alloys have been investigated by H. Unckel who made statistical grain measurements of the degree of deformation of the two phases after various reductions by rolling and also microscopical observations of the flow in the neighbourhood of the grain boundaries. Because of the different relative flow of the two phases, the normal flow is disturbed in the vicinity of their boundaries, and some additional plastic flow must take place in these regions, the disturbance being levelled out at some distance from the boundary. The deformation of the two phases present simultaneously in the material should thus be different from that of each phase separately. The investigation of theimportance and the effects of this interaction of crystals of different phases is the subject of this paper.The deformation of crystals occurs as a gliding of crystal layers following crystallographic laws. In consequence of this slip the crystals composing the material tend to assume a common orientation, i.e. some crystallographic axes tend to become parallel to each other in all the crystals. The type of this preferred orientation depends on the type of the crystal and the working process. Any change in the mechanism of deformation results, therefore, in a change in the preferred orientation. Such a change in kind and degree of preferred orientation will, therefore, also occur if the interaction of crystals in a two-phase alloy gives rise to a mechanism of deformation different from that in the free phases.The present paper describes a study of the preferred orientation, the microstructure and hardness in wires of brass drawn to various extents.The development of preferred orientations in the two phases with increasing reduction was followed up in various layers of the wire.EXPERIMENTAL DETAILSThe experiments were carried out with a commercial 5 S.W.G. wire (0,212 in. diameter) containing: 62·7% Cu, 37·3% Zn, very faint traces...

Jan 1, 1941

THE filter-press, which has done so much for the successful treatment of the sulpho-telluride ores of Kalgoorlie, has a serious rival in the vacuum process, and this paper is written with a view to arousing more interest in the cheaper working of the press, it being doubtful whether its efficiency in extraction can be improved upon.Before proceeding with the actual working of the press, it may be as well to make brief mention of the character of the ore treated at the Associated Northern Blocks, where these notes were compiled.A sample from several weeks' run was taken of the raw ore, with the following analysis...

Jan 1, 1910

Coal has become an enormously important export industry. Owing to a range of mainly natural advantages, Australia has been able to almost treble its exports in a little over the last decade. Australia is now the world's second largest exporter and coal is now the nation's largest single export earner.Despite this very significant growth, Australia's competitive position is in jeopardy.

Jan 1, 1984

In an earlier paper (Stanton, 1953) a brief account was given of the geological environment and structure of the Lloyd Copper Mine orebody, Burraga, N.S.W. The present paper is concerned with the chemical and mineralogical features of the ore from this mine.Investigation has been made difficult because of inaccessibility of the workings, which have been fallen in for many years. The exact positions within the orebody of the specimens described in this paper are known in only a few cases. The specimens examined are from the collections of the Mining and Australian Museums, Sydney, and from material collected by the writer from the upper parts of the mine and from various dumps about the old workings.However, no significant variations in the nature (as distinct from grade) of the ore have been mentioned in the old reports, or by Carne (1908) or Kenny (1928), so it is likely that the specimens examined are reasonably representative of the orebody as a whole.CHEMICAL CONSTITUTIONThe ore is of simple and apparently very uniform composition.It is essentially a copper ore, with minor amounts of zinc and very minor amounts of lead. Plotting of copper against zinc shows a more or less sympathetic relationship between these at least as far as 20 per cent. copper - the highest grade assayed during the present investigation. The trend of the plots indicates a Cu/Zn ratio of about 15/1 to this point. Lead is very low and extremely sporadic, showing no clear relationships with the other metals.MINERAL COMPOSITIONThe principal non-opaque minerals are quartz and sericite, and these are accompanied by smaller quantities of muscovite, calcite and biotite. Quartz is the most abundant mineral, occurring both as a C'onstituent of the country rock a quartz-sericite schist-and as veins. All quartz aggre...

Jan 1, 1955

Removal of Arsenic in Enargite from Copper Ores by Flotation and Leaching in NaHS Media

Sep 13, 2010

Minerals processing needs a step change in energy efficiency. While the search for new technology breakthroughs is important, huge gains are still available by better using existing research outcomes. This potential remains untapped due to a combination of organisational 'silos', inappropriate performance measurement, and poor science in some areas. It is time to see the elephant in the mill.

Sep 13, 2010

By R S. Hamilton, S R. Grobler, M E. Greenway

The progressive development of underground mines frequently requires increased ventilation flow rates through mine shafts that were originally designed for lower rates. Where these shafts are equipped with conveyances running on rope guides, the higher air flow rates adversely affect the lateral motion of conveyances and could cause conveyances to collide with the shaft walls or with one another. Hence the safety impact of higher flow rates requires proper assessment. This can be undertaken by use of computer simulation models to predict the dynamic motion of the conveyances during hoisting. It can also be undertaken entirely by field testing, or using a combination of simulation and field testing. This paper discusses these techniques and makes cautionary remarks about setting an absolute generic maximum flow velocity for all shafts. Approaches to assess existing shafts for increased ventilation flow rates are also discussed.CITATION:Greenway, M E, Grobler, S R and Hamilton, R S, 2017. Safety impact of increased shaft ventilation on rope guided conveyances, in Proceedings Australian Mine Vent Conference 2017, pp 261–270 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By R L. Brathwaite

The gold-scheelite-quartz lodes of the Wakamarina valley were the most productive of the mesothermal gold-bearing areas in the Marlborough Schist. Most of the production came from the Empire City and Golden Bar mines which worked the Golden Bar lode. Only 134 m of its 1800 m strike length are accessible, in the No.2 level of the Golden Bar Mine. A fault has downthrown the Golden Bar Mine section by = 47 m and displaced it left-laterally by 18 m. The lode is a typical ribbon-banded mesothermal vein, averaging c. 1.75 m wide, and enclosing narrow horses of schist country rock. It is composed of bands of milky æbuckÆ quartz with thin laminae of schist. Scheelite occurs in short strings of grains within quartz on the footwall side of the lode and also in small quartz-carbonate veinlets in the foot wall and hanging wall schist. The lode quartz contains only localised traces of pyrite and arsenopyrite. They are more abundant in the wall-rock schist.   The Golden Bar lode lies within a steeply dipping normal fault, which, on its footwall side, is adjacent to a 40 m-wide, shallow-dipping mylonite shear zone. Within 1 m of the lode, the shear foliation has been dragged down to nearly parallel the lode footwall. Wall rock alteration is manifested by a marked increase in K and Rb, which correlate with abundant illite/muscovite and K-feldspar within 2 m of the footwall of the lode. Amphibole, stilpnomelane, and pumpellyite show a progressive decrease towards the lode. As and Sb increase close to the lode, but are at background levels within the lode itself. Enhanced Cr (150-430 ppm) in the quartz, relative to the schists (~40 ppm), suggests that the source hydrothermal fluids passed through and leached mafic rocks, such as the metabasites from the hanging wall of the lode (~400 ppm Cr).

Jan 1, 1995

By Grynberg H, Lindon P, Wardrop J

The Gippsland Basin is unique in Australia in that it is a major resource based industry centre within a sensitive and special environmental context supplying Melbourne, a major urban/industrial environment with most of its energy 'on-line'. The environmental effects of the supply systems are generally local and mostly affect only those who are directly or indirectly dependent on the upstream systems. The major urban metropolis which is served remains largely unaware of the environmental impacts of the system upon which it is dependent, except when specific attention is drawn to them as in the case of the Latrobe Valley Outfall, algal blooms in the Gippsland Lakes, etc. This paper discusses the environmental context within which the energy industries operate, the environmental legislative framework which applies, the likely environmental impacts and some solutions. The energy resources of the Gippsland Basin occur in an area where the physical environment exhibits a wide variety of inherent energy states in its physical and biological regimes. The off-shore regions of the oil and gas platforms has to be able to withstand the wind and wave energy generated in a shallow sea in a confined waterway lying athwart the main current and climatic stream. The coastline includes the delicately balanced quiescent environments of Corner Inlet with its 'wilderness' tourism industry and the powerful surf and long shore drift and dunes of Ninety Mile Beach.

Jan 1, 1992