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The Maddingley brown coal seam at Bacchus Marsh, where mined and bored, tends on the whole to a higher content of volatile matter than the Latrobe Valley brown coals, and this masks the presence of lignitic or earthy coal bands in the bore core analyses. Visits to the Lucifer Open Cut, at Bacchus Marsh, during 1948, revealed, however, a banded condition in the coal seam, as shown in Fig. 1. This banding showed in a face that had been exposed for a considerable period of time, permitting partial drying out and oxidation of the surface coal. The bands consist of different coal types, ,comparable with those found in the Yallournand Latrobe brown coal seams(l).The' light coloured bands in Fig. 1 consist of a buff to light-brown earthy coal of low specific gravity, that closely resembles the pollen coal, that occurs, as similar thin bands in the Yallourn and Latrobe seams. The 40 ft. of coal above the uppermost of these light coloured bands dries out on exposure to a black, closely cracked surface, composed of small dice-like fragments of a lustrous vitrain-like substance, and in every respect resembles the lignitic coal bands of the Yallourn and Latrobe seams.The coal between and below the light-coloured bands develops fewer and more widely spaced shrinkage cracks on drying out, and remains brown in colour and earthy in appearance, resembling the earthy coal of the Yallourn and Latrobe seams.Representative samples were cut of these coals, taking care to exclude surface coal, and analyses were made of them by the Metropolitan Gas Company, through the kindness of Dr. R. S. Andrews, Chief Chemist to the Company...

Jan 1, 1948

By D R Quick

The Goodall gold mine is located 30 km east of Adelaide River, within the Pine Creek 1:250 000 map sheet, at 8 525 000 mN: 750 000 mE, on the AMG grid. The first gold was poured in April 1988 and the mine closed in September 1993, having produced 228 400 ounces of gold from 4.095 million tons of ore, at a head grade of 1.99 g/t. Oxide and primary ore was mined from one large open cut and low grade oxide ore from three smaller pits. The gold mineralisation was discovered in 1981 by means of a helicopter borne rock chip sampling survey, which delineated 13 discrete anomalies. Systematic grid sampling of rock chips outlined an area of 1300 m by 300 m within the 2.0 g/t contour. Over 7500 m of costeaning was used to delineate the A and B-Pod mineralised areas. Geochemical soil sampling played only a minor role in the discovery and geophysics none at all. By the end of 1984, 40 diamond drill holes had been completed and a resource of 3.63 million tonnes at 3.0 g/t calculated. In January 1985, Western Mining Corporation Ltd became a joint venture partner and funded exploration to cam a 60 per cent interest. Additional drilling led to a feasibility study in 1987, based on a Measured and Indicated resource of 4.25 million tonnes at a grade of 2.35 g/t. The host rocks are quartzo-feldspathic wacke and interbedded phyllitic siltstone, of the Proterozoic Burrell Creek formation. The main zone of gold mineralisation, A-Pod, occurs in a sub-vertical vein array, up to 50 m wide and 800 m in length, of quartz and sulphide veins (5-20 mm wide), It is parallel to and on the east limb of an upright, north plunging anticline. Five types of veining have been recognised, with the bulk of the gold mineralisation associated with quartz-pyrite-arsenopyrite and chlorite-quartz-pyrite veins. The gold occurs as particles, from 1-20 micron, as inclusions and along fractures in pyrite and arsenopyrite and to a limited extent in chlorite. The mineralisation is epigenetic and structurally controlled by fractures developed during an earlier folding event. The gold is assumed to have been derived from the underlying sediments of the Koolpin Formation by hydrothermal fluids emanating from the deep seated northern margin of the Cullen Batholith. Precipitation of gold may have been controlled by variations in temperature and pressure.

Jan 1, 1994

By Trueman R

If continuous mining systems are to be successfully applied in metalliferous mines then reliable models will be needed to predict rock cutting machine advance and tool wear rates for effective machine selection before mining commences. Many of the predictive models developed to assess cuttability in situ are over-simplistic. As a result they tend to be both site and/or machine specific. Nevertheless very detailed models have been developed for full face machines which are capable of accurate cuttability predictions in a variety of rock mass conditions and for a variety of machine and tool configurations. However, models to predict productivity and tool consumption for partial face machines are not as well advanced. There is a need to develop reliable models for partial face machines such as Roadheaders, the Robbins Mobile Miner and the HDRK-Wirth CMM, as these types of machine are likely to predominate in a mining environment. The paper outlines the current state-of-the-art for predicting cutting machine performance and the work being carried out within the Centre for Mining Technology and Equipment (CMTE), in collaboration with the Australian mining industry, to advance our capability in this area.

Jan 1, 1995

By McQuade C. V

Mining is an activity which has, in the past, been regarded as often leaving land in a condition unfit for further use. As the need for development that is both economic and ecologically sustainable has grown, so the issue of re-use of land after mining has become significant. During operation it is usual that mine environmental conditions which minimise unnecessary or avoidable environmental impact are agreed with the regulatory authorities . These conditions are usually set down in such a way that they can be interpreted reasonably well by both miners and regulators. However, the conditions to be met by a mining company before it can be absolved of responsibility of a site are often less clear. The close-out criteria by which the success of rehabilitation programs will be judged have received little attention in the past. These conditions are now growing in importance as the costs of rehabilitation of a mine site to an agreed post-mining land use assume greater significance in the economics of mining. This paper briefly describes the status of close-out criteria presently being applied across Australia. A comparison is made with similar guidelines from other countries.

Jan 1, 1994

By Hocking G

For some underground structures, the use of the plane strain assumption in stress analyses may not be justified. The finite element method and photoelasticity have been used to obtain complete 3-D solutions, but, for various reasons, neither method has found universal use. The boundary integral equation method (B.I.E.M.) can be more efficient and economical than the finite element method for 3-D problems involving large volume to surface area ratios. A B.I.E.M. program developed for calculating stresses and deformations in infinite elastic media has been used to determine the 3-D distributions of stress around T- and Y- junctions of circular tunnels in stress fields in which the ratios of horizontal to vertical stress are 0, 0.33, 1.0 and 2.0. For the T- junction considered,stress concentrations at the intersection are approximately twice the plane strain values. Except where horizontal field stresses are high, the stresses in both tunnels approximate the plane strain values at about two tunnel diameters from the point of intersection of the tunnel centre lines. The stresses in the two branches reach those for the corresponding plane strain, two parallel tunnel case two diameters from the point of intersection of thq inner tunnel walls. Very high stress concentra- tions occur in the pillar of rock between the inner tunnel walls near the point of intersection.

Jan 1, 1976

By C Czerny, T Elkington, L Lorenzen

The Dutwa Nickel Project is a nickel laterite atmospheric leach project located in Tanzania that has been under development by African Eagle Resources plc (2012). A bankable feasibility study (BFS) has been progressed to evaluate mining of the resource (107 Mt at 0.92 per cent Ni) followed by hydrometallurgical processing on-site to make a mixed nickel-cobalt intermediate product. The unique relatively high silica contents in the Dutwa deposits, as opposed to limonite, which is more commonly occurring in nickel laterites, presented the possibility for beneficiation of the ores to enhance the leach feed nickel grades and provide economic benefits in terms of operating and capital cost efficiencies.Geometallurgical relationships, based on the results of an extensive variability metallurgical test work program for beneficiation and leaching, were developed for the BFS, which resulted in an improved understanding of ore classifications within the deposit and their responses. The geometallurgical information obtained has been instrumental in making key preliminary techno-economic decisions, such as forecasting whether or not mined material should be beneficiated and was ultimately used to drive the mine plan towards the prioritisation of areas within the deposits that delivered the best cost efficiencies and overall project economic outcomes.CITATION:Elkington, T, Lorenzen, L and Czerny, C, 2013. The use of geometallurgical relationships in process route selection and mine plan optimisation for the Dutwa Nickel Project, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 207-216 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By Nilsson C

Man has always been and will always be part of his environment, in ,a good, bad or indifferent manner. Until quite recently, this environment has been the atmospheric boundary layer above the land masses, and to a limited extent the air-sea interface of the oceans. Since the days when he lived in caves, he has built up a wealth of observations on these two environments,-with ever-increasing scientific precision which unfortunately until quite recently was completely insufficient for modern capabilities of data analysis. Consequently, in a sense, he has left in his wake thousands of years of missed, opportunities for making exact observations and increasing his understanding. The data of the past are lost and he has to be satisfied with what he can assemble from now on when his environ- ment, largely as a result of his actions, is exhibiting more and more rapid variations in time; in other words, time series of observations of phenomena are required, the length of which is critical for most purposes of analysis.

Jan 1, 1970

By R C. Morris

Secondary microplaty haematite in its variety of styles and generations is the defining component of the high-grade banded iron-formation (BIF)-hosted iron ores of the world that are dominated by martite (M; - haematite pseudomorphs after magnetite). The term microplaty haematite (mplH) was introduced during the CSIRO-AMIRA 1976-1994 iron ore program, and was used to differentiate the then main export martite-microplaty haematite (M-mpl H) ore types of Tom Price-Whaleback and Paraburdoo (Paleoproterozoic), from the newly exploited, more prolific supergene martite-goethite (M-G) ores (Mesozoic-Paleocene) of the Hamersley Province that are now the major Hamersley iron ore exports.Morris (1980, 1985) suggested that the most important genetic factor that distinguishes the two main ore types was regional metamorphism of Paleoproterozoic M-G ores at temperatures normally related to diagenesis (ca 80 - 100°C). As temperatures increased, mplH grew in goethite both spontaneously as well as by nucleating on martite and other pre-existing haematite. Because the conversion of goethite to haematite involves a ~27 per cent reduction in volume, the crystals probably grew within microvoids of their own creation, with iron transfer through water resulting from the process itself, a local hydrothermal process requiring no introduced hypogene fluids.Barley et al (1999) and Taylor et al (2001) concluded instead that oxidation of introduced siderite in hydrothermally metasomatised BIF ‘protore’ resulted in mplH + ankerite by reaction with heated meteoric fl uids. This postulated ‘protore’, still preserved locally at Mt Tom Price, was described during the CSIRO-AMIRA program as local post-ore BIF metasomatic residuals. These new hypogene-meteoric concepts for M-mpl H genesis have formed the basis for a range of varying local and international models that currently dominate the literature of iron ore.No valid petrographic data supporting the hypogene-supergene modelling was found but petrographic images of goethite-related mplH growth in a range of different environments are shown.

Jul 11, 2011

By K Saito, M Hasegawa

Removing sulfur and phosphorus from molten iron can be expressed by the following reactions, respectively. [S]Fe + (O2-)slag = (S2-)slag + [O]Fe [P]Fe + (3/2) (O2-)slag + (5/2) (FeO)slag = (PO43-)slag + (5/2) Fe(liquid) These equations indicate that desulfurisation and dephosphorisation have opposite oxygen potential conditions. If a small amount of desulfurisation slag not removed is carried over to dephosphorisation process, the reaction of sulfur mentioned above proceeds toward left hand resulting in increasing sulfur content in molten iron. For better understanding of such re-sulfurisation reaction in hot metal pre-treatments, the present study aimed at evaluating the effect of iron oxide on the sulfur distribution ratio between slag and hot metal. To measure sulfide capacities and FeO activities simultaneously at temperatures below the melting point of pure iron, CaO-SiO2-FeO and CaO-Al2O3-FeO ternary molten slags were brought into equilibria with copper-iron-sulfur liquid alloys, and the equilibrium oxygen partial pressures were determined with an electrochemical technique involving the stabilised zirconia solid electrolyte. The experimental results showed that the sulfide capacity increased with an increase in FeO content, and this trend was consistent with the fact that FeO was basic. Although the addition of FeO raised the FeO activity and oxygen potential, the calculated value for sulfur distribution ratio between slag and hot metal increased with increasing FeO content.

Jun 19, 2024

By Dyne GD

From experience in the design and operation of power station combustion facilities in most mainland Australian States, involving a wide range of black coals and lignites, and in the specification and procurement of coal supplies for power station use, techniques for the optimisation of coal resource development and power generation utilisation have been developed to ensure compatibility between characteristics of the selected coals and power station design. These techniques include computer data bases for resource data handling and computer simulation of coal-fired boilers for determining coal property cost effects. Data Base Systems allow results of coal analyses to be efficiently handled, to assist in the review of the relevance of resource data to the coal sections proposed to be mined and the coal fractions proposed to be marketed. Data Base Systems also facilitate the marshalling of coal quality data into basic utilisation format to enable a proper utilisation review and analysis of the certainty and scatter of coal properties. Computer simulation of the effects of different coal properties on the capital and operating cost of power stations is achieved by establishing conceptual design parameters of the major items of plant to relate the variations in coal specification to equipment size and type. Variations in power station budget costs can then be determined using the computer model for variations in coal specification.

Jan 1, 1983

By Sehic O. A

Geology can be the root of evil or a source of bliss; there is a choice; to ignore geology is at a mine's peril.Risk can be minimised and profitability maximised by the application of a detailed understanding of geology, alteration, structure, mineralogy, chemistry, fabric and texture.Geology is dynamic, not static.The impact of geology is pervasive.The integration of ore quality control with grade control is one strategy for improving the utilisation of both the mineable reserves and existing plant and equipment. Grade maintenance is but one constraint on the problem of how best to blend the ore. Other ore characteristics such as mineralogy, hardness for grinding, and pulp fluidity or density for slurry size classification can be included to explore alternative blending Strategies.

Jan 1, 1993

Mining software systems have provided a basis for integration of resource, survey, and design functions. They can similarly provide a basis for incorporating ground conditions into the process.Exploration and mine geologists have a prime role to play in this process, extending their responsibilities further across the geological spectrum, into exploration of ground conditions, analyses of results, and assessments of their implications for mining. Ground conditions are as much a part of the geology of a prospect or mine as its mineralisation, and can have critical imnlicationa for mining.

Jan 1, 1993

By R Gilbertson, N Freeman

Metallurgical accounting is key to the control and production planning process of any mining operation. This is even more crucial for complex operations involving mining, concentration, smelting, refining and marketing. The tracking of multiple metal product and contaminant components through the operation can improve process predictability and inventory management. Appropriate use can be made of æhigh quality dataÆ for strategic reserve utilisation, mining operations, milling operations, etc. This information enables the optimisation of all aspects of the mining and processing operations. This case study discusses a metal balance implementation for WMCÆs Olympic Dam operations; a large integrated mining, concentration and refining operation, which used an existing off the shelf statistical data reconciliation package developed for the oil industry. It was extended to track and balance the metal co-products across the entire integrated mining, mineral processing and refining plant. The key benefits discussed are tight integration with existing data collection systems, formalisation of previously informal processes, and leveraging the development and support available for a widely used package. The project provided a solution for the site metallurgical balance spanning the mine and processing plant. The solution facilitates a bridge between the planning and production worlds, using a common data model across the site.

Jan 1, 2002

By Bockhorst R. W, Christopher D. A

Over the past fifteen years, horizontal drilling in coal seams for advance degasification has become an established practice in the United States of America. Consolidation Coal Company pioneered the development of the horizontal drilling system and licensed the technology in the U.S. A. and to Du Pont (Australia) for commercial production. This paper discusses the most recent developments in the equipment design, especially the borehole telemetry system, known as the Downhole Drill Monitor (DDM).

Jan 1, 1988

A survey of leaching systems for the dissolution of gold has been undertaken and their advantages and disadvantages evaluated both from their effectiveness at leaching and their compatibility with carbon- in-pulp (CIP) and resin-in-pulp recovery. In the near future it is almost certain that cyanidation in some form will remain the leaching system of.choice although economic and environmental pressures could see the introduction of other leaching systems particularly for treating refractory gold ores. The most likely alternative leaching systems appear to be acid chlorine, acid thiourea and ammoniacal thiosulphate. INTRODUCTION High grade reserves of readily recoverable gold ores are gradually being depleted which, inevitably, must create a greater awareness amongst gold producers, of the efficiency and, in some cases, the suitability of present day metallurgical processes for treating low grade, complex and refractory deposits. One of the key steps in the extraction of gold is the dissolution of the metal using chemical reagents which, ideally, should be cheap or recyclable, selective, non-toxic and compatible with down-stream recovery processes. In practice, meeting all these critera is difficult - if not impossible - particularly in view of the stringent environmental impact requirements which must be met Nowadays.

Jan 1, 1982

By Ryan CG, Cousens DR, Griffin WL

The proton microprobe is developing into a vital tool in the geosciences, through its high sensitivity for in-situ detection of trace elements in the ppm regime. This paper will describe the instrument at the CSIRO Heavy Ion Analytical Facility at North Ryde, including features crucial to its successful application in the geoscience. Examples of applications in the basic geoscience and mineral industry related research are described briefly. Conditions required for widescale applications in the minerals industry are Discussed.

Jan 1, 1989

IT will be noticed, from the following contributed papers on the various plant, what an infinite number of parts are required to be kept in active operation in order to derive a resultant product of commercial value from the ores and materials received at the works. Crude ores and concentrates, in every degree of complex structure and resistance to treatment, are arriving daily from near and distant places, moreover their metallic contents are so varied that an outsider, unacquainted with the operations, would naturally wonder how it is possible that the rare elements are to be sorted out and classified into their true order, to meet industrial requirements.The proposition is necessarily not a simple one and owners of mining properties have naturally refrained from smelting their complex ores on account of the technical difficulties of attaining high efficiency and recovery of the metals, where limitations are imposed in procuring a variation of ores that lead to the best smelting and refinmg result. This difficulty obviously imposes many disabilities on the smelter, who is prepared to accept all such complex ores, and it may be said that were therenot available a large weekly supply of lead concentrates from the company's own mine at Broken Hill, of standard quality, much of the material being treated in the world today would certainly not be marketable.In order to sustain full efficiency, each section of the works must maintain its.true balance and synchronize with the requirements of such other departments as are dependent on its partially treated materials. This harmony of operations is not only imperative as regards tonnage output, but also relies on the condition of the resultant treatment by each plant, no large variations being permissible.The various officers are, therefore, dependent on one another to keep the order of the operations flowing regularly. This is accomplished by constant intercommunication and observation, as...

Jan 1, 1918

Attempt has been made to determine the nature of charge on activated carbon surface by studying the electro-kinetic properties of the carbon in the presence of cations, anions and aurocyanide solutions. The zeta-potential measurements were made in the presence of individual ions and also in combinations. The cations and anions chosen were those commonly associated with gold bearing ores in Kalgoorlie area. It was found that the iso-electric point of Norit Carbon was at pH 4.45; below this pH the charge was positive, while above, it was negative. In the absence of gold cyanide solutions and in the presence of individual cations the i.e.p. shifted to the alkaline range (pH 7.2-8.5) while in the presence of anions the i.e.p. was shifted to less than pH 3.5. In the presence of aurocyanide solutions, the iso-electric point was still in the acid region irrespective of whether anions or cations were present. The probable mechanism for such a behaviour has been attempted after measuring the specific conductivities of solutions before and after gold adsorption, by studies using the electron- probe-mirco-analyser, and S.E.M. on the carbon surface.

Jan 1, 1982

There is a difference in design aspects between steel linings and rubber linings for grinding mills. The basic design rules for rub- ber are described as well as the liner designs for different applications.

Jan 1, 1978

By Slater R

The initial planning and detail design phase leading to the development of a 7.5 m internal shaft to service the deep 3000 and 3500 copper orebodies at Mount Isa, Queensland is well advanced. The choice of internal shaft access was made over alternative methods such as a decline from existing levels and borehole hoisting. The resulting access development requirements and shaft configuration for production have been determined. Several techniques are being studied for shaft development. These include the application of blind shaft drilling and large hole reaming methods as well as conventional sinking techniques. As the 3000/3500 Orebodies extend from 1000 metres to more than 1800 metres below the surface, high stress conditions and ground temperatures ranging from 45CC to 62CC are anticipated. The effect of these on the methods being investigated to create a favourable working environment will influence the final choice. Exploration diamond drilling is in progress to confirm the geology of the orebodies so that planning for their extraction including refrigerated ventilation concepts can proceed.

Jan 1, 1982