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By R M. Smart, A T. Harrison

Backfill systems using unconventional cementitious binders have been successfully used in relatively deep and hard rock tabular mines for longwall, scattered stoping and shaft pillar removals. Two unconventional cementitious systems are discussed: A ground granulated blast furnace slag (GGBS) with an activator containing lime. This has been used with a total tailings æstableÆ slurry at a relatively low dosage of less than seven per cent, by mass, based on dry solids. The room and pillar stopes supported with this fill were up to 20 m high and the tailings were relatively high in pyrite. A GGBS binder plus a silicate based activator and gelling agent that virtually eliminated all water drainage (and hence post filling shrinkage). The system used a slurry, but the addition of the activator created a final placed product that had the behaviour of a paste. The system has been successfully used for almost ten years in the following applications: stoping widths (mining heights) above 1.6 m; and shaft pillar removals in seismically active areas at the end of the life of the shafts. This paper discusses the technical merits and costs of the systems and compares them to other fill systems (including true paste systems). the acceleration (normally g, 9.81m/sec2) is increased to a significantly larger (but generally unmeasured and unknown) value, as shown in Figure 1.

Jan 1, 1998

For small particles of niekel flotation eoncentrate (av. size 50 pm) the predominant heat transfer mechanism under suspension smelting conditions, prior to ignition, is conduction from the gas and not radiation from nearby hot bodies. Results of laboratory tests using gas temperatures 380-700°C and furnace wall temperatures 380-1100°C were in accord with heat transfer theory. In practieal flash smelters earlier ignition, and hence better utilization of the space in the shaft, would result from introduetion at the top of the shaft of gases hotter than the ignition temperature of 500-600°C.

Jan 1, 1979

The point of the anode effect on carbon anodes of dcfincd surface area. during electrolytic decomposition of alumina dissolved in molten fluorides. has been determined from current-voltage curves. The reproducibility and accuracy was found to be better for cell voltage than anode current density. Results have been obtained for the effect of alumina concentration temperature and carbon type. The point of the anode effect was strongly dependent on both the alumina concentration and the carbon type. For high alumina concentrations it has been found that the anode effect approaches reversibility. From these results it is concluded that co-evolution of CO, and CF. occurs prior to the onset of the anode effect. The anode effect results when the CF, content becomes sufficiently high for the melt not to wet the electrode surface and is maintained because of the slow desorption of CF, and the high electrode potential that results.

Jan 1, 1967

The theme of this paper is the development of-the project feasibility study which includes discussion of the work which is carried out in preparing the project feasibility study, the necessary evaluations and structures that are employed to ensure that not only does the feasibility study itself stand up to scrutiny and is sound, but also that the investment the company is proposing to develop, "the project", is an investment decision which will represent good returns to the company. This theme is particularly relevant when there are competing divisions within the company and only limited cash resources are available to make the correct investment decision. Thus various potential investments may be evaluated against each other to determine which project will be given the go ahead for development. This paper will particularly focus on the various investment analysis techniques that are used and discuss the work that is required in preparing the project feasibility study and specifically the interaction of the project team members and the thought process that must be undertaken to complete the project feasibility study. Finally comments will be made on tax planning issues particularly with respect to taxation of gold production to be introduced in January 1991. Some ideas are presented which may help and possibly improve the financial position of the projects being reviewed. Further, it is suggested that the thought process which goes with the financial engineering aspects of a resource project can be widened to take account of taxation issues and tax planning to ensure the rise of the project feasibility and hence the decision to proceed to development by the project sponsors.

Jan 1, 1990

On the basis of field observation, four principal styles of hydraulic breccia are recognised, and their characteristic features noted. In practice, hybrid styles are most commonly encountered. Numerous examples will be illustrated during the oral presentation, and the potential for definition of a formative environment is emphasised. In one example presented, it is suggested that more than 50 episodes of hydraulic fracturing can be recognised. In all cases at least sane useful conclusions can be drawn in the context of modeling for drill targets.

Jan 1, 1987

By E J. Cowan

Efficiency demands that mine geologists devote the most time to tasks where they can have the biggest effect on production. One of the most time-consuming tasks is geological interpretation of the orebody and turning this into a block model for the planning engineers.The current best practice for mines that require a geologically constrained resource model involves capturing the interpretation of geologists as three-dimensional (3D) wireframes. However, there is significant overhead in the production of valid wireframes from sectional and plan interpretations. This overhead consists of the mundane tasks of digitising polylines, then building 3D wireframes and validating them. While software can simplify this task, the current process is not the best use of a geologist’s time. Under time pressure exerted by planning engineers and the time required for modelling from polylines, geologists are forced to roll-up the presence of other elements or impurities into the interpretation and encode them in the polylines, even though it is often desirable to consider these other factors separately.While it might seem unlikely that mine geologists can produce constrained geological models without the intermediary of wireframes, the technology to accomplish this is getting closer.In this paper, the results of a trial at the Savage River magnetite mine, which is owned and operated by Grange Resources Ltd, are reported. The trial was for a ‘direct-to-block’ implicit geological modelling method. The focus was on creating a geological attributed block model from drill hole geological log data; resource estimates were not determined. The categories modelled were air, waste, low-grade ore, medium-grade ore, and high-grade ore. The block model outputs either resulted in a proportional block model (categories expressed as percentages within equivolumetric blocks) or a sub-blocked model (parent block and one sub-block), which is the preferred block model output at the Savage River mine. When compared to the traditional best practice modelling method, which takes 43 work days, the wireframe-free modelling method took only 26 hours from initial modelling, using both exploration and grade control data. An update using appended drill hole data is achievable within one day. These results represent time savings of more than one order of magnitude compared to the traditional workflow, and, as such, these figures merit serious consideration for the use of the direct-to-block modelling approach at other operations.With these time savings, geological and estimation models can be kept updated constantly; geologists will not need to set aside two months for quarterly or half-yearly modelling of the drill hole data for resource review. Such dramatic time savings will allow for the better use of highly skilled geologists, who are in short supply in the current market, and will also impact directly on downstream mining engineering workflows.

Aug 22, 2011

Interest in industrial minerals in recent years has increased to such an extent that it has taken them into the mainstream of the Australian mineral industry. Notwithstanding that time series data on the values of production, exports, and imports show that industrial minerals are overshadowed by metals and energy minerals, their contribution to the national economy is important and more significant than would seem to be indicated by the statistics. Whereas the ex mine value of metals generally includes some processing (at least to a concentrate stage), most industrial minerals are valued at little more than their extraction cost, in addition to which such costs are generally low because most industrial minerals are exploited in low-cost surface operations. Consequently, values of mine production of metals and industrial minerals are not strictly comparable in that values of mine production of metals tend to be overstated Short term growth of the industrial minerals sector is assured because of several new projects already commissioned but not yet reflected in the statistics. Longer term growth is also assured, based on various other major projects that are likely to come on stream in the early to mid 1990s.

Jan 1, 1989

Ultrasonic Extinction for High Resolution Particle Size and Concentration Analysis

Sep 13, 2010

By S Robinson, R Perkins, D Barrett, D Kepert, C Fowers

The discovery and delineation of significant mineralisation in the Eliwana region continues Fortescue Metals Group’s strong exploration success. In the decade after the first hole was drilled into Christmas Creek in mid-2004 a total of over 11 Bt of hematite-goethite mineralisation have been delineated supporting the raising of $13 B, construction of five mines, 620 km of rail and a five-berth port. As of June 2014, Fortescue was shipping at the rate of 155 Mt/a. The area including the Eliwana and Flying Fish deposits is one of a number of future growth opportunities that Fortescue is currently evaluating.The Eliwana and Flying Fish deposits occur on the south dipping limb of the Brockman Syncline/Jeerinah Anticline. The Eliwana group of deposits are hosted by the Brockman Iron Formation with the Flying Fish/Broadway group hosted by the Marra Mamba Iron Formation.Structurally the area is dominated by moderate southerly dips of the regional dome and keel style folding. The regional limb is locally cross-cut at a small angle by asymmetric north facing Ophthalmian folds trending 110°. These fold sets, in part, preferentially host subsequent supergene mineralisation. Faulting is only locally apparent.Early phases of exploration commenced in 2006, with mapping of Flying Fish and reconnaissance drilling in 2007. However, due to the concurrent discovery (Clarke et al, 2009) and subsequent fast tracked development of Solomon channel iron deposit and Firetail bedded iron deposit (Simpson et al, 2011) priority was placed on developing Solomon due to its relative proximity to existing Fortescue infrastructure. Staged follow-up drilling of both Marra Mamba and Brockman targets at Eliwana was progressively undertaken from 2008 onward.As of 20 May 2014 a total of 1494 reverse circulation (RC) holes for 54 248 m and 13 diamond holes had been completed, resulting in the delineation of a Mineral Resource of 740 Mt. Exploration via mapping, drilling and metallurgical evaluation of adjacent prospects continues with additional resources expected in the future.CITATION:Barrett, D, Perkins, R, Kepert, D, Robinson, S and Fowers, C, 2015. Geological setting of Eliwana and Flying Fish deposits along the north limb of the Brockman Syncline, Hamersley Province, Western Australia, in Proceedings Iron Ore 2015, pp 219–228 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

The Physiographical Features of the Region The Middleback; Range proper, from the Iron Duke in the south to the Iron Prince in the north, extends in a meridional direction for 21 miles, but may well be taken to embrace also the Iron Knob and Iron Monarch prominences so that the total length of the Range is 37 miles.Although no great altitudes are reached, the slopes of the high country are steep and the Range stands out prominently above the peneplaned surface of upper Eyre Peninsula. The Range is built up of sub-parallel ridges at some places, and its continuity is interrupted by transverse breaks or gaps resulting from normal stream erosion and corrosion during earlier periods when precipitation was heavier and streams were more active. Traces of high-level gravels remain on the flanks of Kimba Gap. A former mature stream on the western side of the Range has had its lower reaches blocked by sand and the old stream channel has been converted into an eiongated basin of internal drainage. The sand dunes in this area appear to be practically stationary at present, being fixed by mallee vegetation. Their trend is west-northwest.The relief of the Range is regarded as having been determined primarily by meridional strike faulting and selective silification of some of the beds. Dip faulting on the Iron Duchess leases has produced subsidiary features only.The Rocks of the Region: In order that some of the points made in the discussion of the genesis of the ore bodies may be appreciated it is necessary to consider the stratigraphical succession and the igneous types represented. This classification may be...

Jan 1, 1949

By Ray H. S, Galgali R. K

It is well accepted that the blast furnace will continue as the main route for iron-making for many more years. However, its limitations have motivated researchers to look for alternative routes, particularly, those where non-coking coal is used for liquid iron production. Smelting reduction (SR), where coal and oxygen are used to produce liquid iron and power is now receiving serious attention. Several smelting reduction reactors are now operating in pilot plant scale and one or two have reached commercial status.

Jan 1, 1999

This study explores two evolving 3D surveying technologies, photogrammetry and laser scanning, and applies them to deformation monitoring of rock faces and mine highwalls. A quantitative analysis focused on 3D coordinate determination is performed. Furthermore, a qualitative assessment directed at the practicality and viability of each system operating near a rock face or in a mining operation is undertaken to reveal one systemÆs deficiencies over the other. Two photogrammetric and four laser scanning surveys aimed at optimising accuracy and precision within a short period of data acquisition are conducted on the rock face at Organ Pipes National Park, Keilor, Victoria. The accuracy and repeatability of each survey is determined using a combination of iWitness photogrammetric, and Cyclone laser scanning software. The 3D coordinates of targets placed on the rock face are determined by triangulation and resection principles within a bundle adjustment. The coordinates determined by each system are then compared in a 3D transformation. Controlled deformation conditions are established to determine the precision to which each system can detect movement in the rock face. An object of known dimensions is placed on the rock face to simulate deformation. The relative orientation of images taken for the pre- and post-deformation photogrammetric surveys provide an overall 3D point accuracy of 1.255 mm and 1.804 mm respectively. A 3D transformation shows discrepancies of less than ¦22 mm (RMS) between the geometry of the photogrammetric and laser scanning models. Both systems are able to detect the simulated deformation to a precision of 50 mm. This work also identifies how to obtain millimetre accuracy for 3D coordinate determination of rock faces, thereby providing a quality data set for surveyors, geotechnical engineers and mine geologists. Photogrammetry is shown to be a mobile, time and cost-effective technique that is more amenable to mining operations than terrestrial laser scanning. However, both systems demonstrate that they are capable of detecting movements that may lead to failures in the rock face, and possibly endangering human life. The implications are significant for surveyors, geotechnical engineers and mine geologists working in mining operations where enhanced safety conditions, increased productivity and lower operational costs are important considerations.

Jan 1, 2009

The Government signalled its intention in the Economic Statement on 17 December 1987 to improve the fairness of the taxation system and to facilitate the process of economic adjustment by: removing tax concessions that benefit some taxpayers at the expense of other taxpayers,ensuring that those who can afford it shoulder their fair share of the tax burden,securing a revenue base which will provide sufficient resources to maintain effective social services,reducing artificial protection and concessions that discriminate against some sectors, and encouraging confidence through an economic environment with a medium-term orientation. The Government has clearly stated to all sectors that tax preferences will be phased out and businesses need to look inwardly to their investment policies if they are to survive in an open economy. This paper will address the effect of these Government objectives on the taxation structure for all forms of mineral exploration in New Zealand. The present tax structure will firstly be analysed, in particular setting out the tax advantages available to the industry. The effect of changes to the tax system within the recent past which relate to mineral exploration will then be examined. Finally the paper will address the question of possible future changes, particularly in the light of Government's intention to move towards a tax system which does not provide an advantage for any one sector of the economy.

Jan 1, 1988

The rapid advance in the adaptation of scientific knowledge to the treatment of ores, resulting in improved chemical and metallurgical processes, has enormously increased the possibility of working lodes profitably, which a few years ago were passed over as unpayable. By the discovery of chlorination, and later of "Cyanidation," by the highly improved methods of concentration, and by the rapid advance in our knowledge of smelting (for which we are greatly indebted to Americanmetallurgists), and by the gradual replacement of scientifing principles and enlightened management, for rule-of-thumb methods formerly in vogue, many large low grade bodies have been opened, and are now paying dividends, which were,twenty years ago, looked upon as hopelessly unpayable. It has been more especially in these large low grade ore bodies, that modern methods have been benefical; for small lodes must be rich to pay at all, as they cannot be worked on the same gigantic scale, but even in these a percentage of metal is saved which formerly was absolutely lost.To make these large deposits remunerative it is, however necessary to try and find the point of greatest economic advantage, to handle the ore in vast quantities, to erect huge plats to treat it, to substitute automatic appliances for hand labour as far as possible, and to combine several processes supplementary to one another, so that ore which is not amenable to one process, shall be saved, by another; and by doing...

Jan 1, 1901

By D McLaughlin

This paper points to the timely importance of commencing a centrally recognised perpetual collection of mineral specimens in the Northern Territory which has as one of its objectives the collection and preservation of Northern Territory minerals of scientific, educational and heritage value. Currently in the Northern Territory there is no government department or institution that has a resourced coordinated state-wide objective to collect and document collectable mineral specimens. Specimens held in storage by the Department of Mines and Energy and the Museum and Art Galleries of the NT are not catalogued and owe their existence to fortuitous circumstances, not as a result of a planned systematic scientific approach to mineralogy. Northern Territory mineral species and unique specimens have and will continue to be driven to extinction while no central and active, recognised repository exists. This situation persists despite the fact mineral production is the Territory's largest income earner. The paper presents the arguments that hopefully will assist decision-makers to commence development of a state mineral collection lodged within an appropriate institution in the Northern Territory.

Jan 1, 1994

A general outline of the significant features in the quality and manufacture of the more common refractories is given. Where possible, linkage between quality development and control and service applicationhas been shown and explained. INTRODUCTIONThe refractory industry is no stranger to change. New processes and revision of old processes in other industries are the harbinger of new and revised products in refractories.Few of the changes are dramatic; generally they are evolutionary rather than revolutionary. New developments are additional to, and inclusive of, established practice.Therefore in this paper it is necessary to repeat much of what is already known in order to show the development taking place.FIRECLAY REFRACTORIESGeneral technology Fireclay refractories are the most common, the most varied and the most versatile of all refractories. Virtually any composition of silica and alumina up to the composition of kaolin is possible. For purposes of comparison they may be classified in the Continental fashion in accordance with chemical composition or in the American way according to "duty". That the two methods are equivalent is shown by an inspection of the alumina-silica diagram of Bbwen and Greig (1924). 'Fireclay refractories are composed of a glassy and a crystalline component derived from the chemical and physical nature of the raw materials used in their manufacture.

Jan 1, 1961

Copper ores are widespread through the Lachlan Geosyncline in New South Wales, but the size of the orebodies is generally small. The largest deposits occur in the Cobar district where an iron-rich copper ore type has been developed in Silurian sediments. Similar de- . posits to the south in the Nymagee-Mt. Hope-Melrose districts are related to quartz feldspar porphyries of probable Upper Silurian age. Deposits to the east in the Tottenham-Girilambone districts are less complex mineralogically and are possibly related to an ultra-basic source.Copper mineralization in the Highlands further to the east is often developed in Ordovician andesite or MiddleUpper Silurian acid volcanic sequences. The deposits in andesite contain considerably less galena than those in the acid extrusives; a small proportion of the mineralization in the latter has texture, mineralogy, and geologic setting analogous to the Captain's Flat copper-Iead-zinc deposit, for which both syngenetic and epigenetic origins have been proposed. Very little copper mineralization occurs within granitic material, even though rocks of this type ranging from Silurian to Carboniferous in age crop out through much of the geosyncline, and the extent of the metal contribution from plutons to the deposits in volcanics is open to question. Numerous deposits are known in the contact zone around Mid-Devonian and Mid-Carboniferous granites, however, and the formation of these orebodies has undoubtedly been influenced by plutonic activity. Small occurrences of copper with associated minor nickel sulphides are developed in a narrow serpentinite belt of possible Lower-Middle Devonian age in the southern section of the Highlands.

Jan 1, 1970

By Delahant A. B, Dworski M

From the Saranac Laboratory for the Study of Tuberculosis of the Edward L., Trudeau Foundation, Saranac Lake, New York:We are assembled to honor the memory of our friend and colleague, Donald Cummings, one of the founders and a past president of the American Industrial Hygiene Association. I deem it an Unusual privilege to have been asked to give this first memorial lecture and hope that what shall have to say may be worthy of the occasion. It is fitting that we should discuss here the subject of Silicosis to which he devoted such a large part of his life and it is doubly fitting, I think, that I should report to you an extended series of investigations carried on by his associates at the Saranac Laboratory.The subject of silicosis may seem hackneyed to this audience which is so familiar with the tried and accepted methods of prevention and control.But in spite of our efforts, the condition is still with us and unfortunately is still being produced in many places. In industries that now maintain good control of dust, fresh cases are appearing on annual re-examination, whose major exposure date back to the days before the hazard was recognized.A few new employees, with apparently ineffective upper respiratory protection against inhaled dust, develop silicosis precociously in environments that are comparatively harmless to their fellows. In plants that have relaxed their vigilance under the urgency of war production schedules, conditions again prevail that will produce, disease in the future.Silicosis acquired new interest with the announcement by Denny, Robson and Irwin(1) in 1937 that it could be prevented by the inhalation of powdered metallic aluminium. It so happened that without knowledge of their work, we at the Saranac Laboratory had for some months been conducting similar experiments with one of the hydroxides of aluminium.Quite independently we discovered that hydrated alumina would also protect animals against quartz. Our approach to the problem had been empirical; we were trying to neutralize quartz particles by coating their surfaces with an insoluble material following the lead of Kettle who in 1932 had shown that this could be accomplished with iron. He neglected to describe his method and the chemist who prepared his coated...

Jan 1, 1945

By P Rubie, B Morgan, J Russell, C Stewart

The relationship between efficient liner exchange, concentrator availability and concentrator profitability is well documented. Russell Mineral Equipment’s (RME) relationship with OZ Minerals’ Prominent Hill site personnel enabled sound collaboration between the two parties. Both parties worked together to identify the sources of productivity and efficiency loss and developed solutions to reverse them.This paper chronicles the identification of production inefficiencies and the resulting removal of mill relining from the critical path through the materialisation of mill relining optimisation strategies. Furthermore, this paper outlines other recent mill relining optimisation strategies developed by RME and tested at Prominent Hill, to demonstrate and achieve further productivity, efficiency and safety improvements.CITATION:Rubie, P, Russell, J, Morgan, B and Stewart, C, 2017. Mill relining optimisation – a story of collaboration, in Proceedings MetPlant 2017, pp 335–345 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By K Pery, J Leahy

Established metallurgical plants operate in a complex environment of interdependent drivers including technology change, operating and maintenance practice, evolving markets, HSEC requirements, statutory and plant requirements, personnel turnover, ore supply, and financial conditions, to name a few. A successful optimisation program should comprehend these factors and drive towards not only lower operating costs, but also higher rates of return for a given level of investment. Optimisation programs have the potential for very high rates of return on capital that Greenfield projects rarely have. This paper presents a robust strategy and methodology for plant optimisation initiatives as well as a case study of how it was implemented at the QNI Yabulu refinery in Queensland, Australia by an integrated team of researchers, engineers and operators. The methodology is premised on the fact that nobody knows the production asset as well as the current operating team. It covers the optimisation process from ideas generation, various stages of selection against the agreed criteria, development, including testwork, funding approval and implementation. It highlights the benefits in the use of integrated teams, the establishment of a sound project basis, and a diligent, phased approach.

Jan 1, 2004