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The production of synthetic crude oil requires a suitable coal or a coal extract modified by hydrogenation for pyrolysis. Existing classifications are broadly based on historical and current needs. One, Seyler's, is based on a visual display which can be used to present petrographic bounds. The analysis of the coal extracts from solvent hydrogen-donor testing allows an experimental limit to be described and a plant limit to be indicated. Australian black coals are discussed within these petrographic and plant bounds and their limitations as a feed for the production of synthetic crude presented. Potential uses for the aromatic liquid products are suggested. The application of the diagram as a screening procedure for sub-hydrous coals is described.

Jan 1, 1975

By E V. Man, O N. Savassi, J-P Franzidis

In flotation, the property that is exploited to effect the separation of a mineral from an ore is referred to as its floatability. Assessment and quantification of ore floatability is of fundamental importance in modelling and simulation of flotation circuits. This paper describes the design, construction and operation of a new laboratory flotation rig that has been developed at the Julius Kruttschnitt Mineral Research Centre (JKMRC) to determine the floatability of different ores on a small-sale. The rig is designed for continuous operation. The major features of the rig are highlighted in this paper. An unique characteristic of the rig is a 9.1 L conditioning vessel. This provides a mixing regime close to plug-flow which avoids complications such as different collector coverages for similarly sized particles (which would considerably increase the complexity of ore floatability determination). The main advantages of this rig when compared to conventional batch flotation cells include better control of the chemical environment and the ability to determine froth recovery, entrainment and water recovery with increased accuracy. Preliminary tests undertaken with a high-grade lead/zinc ore from BHP Cannington are presented demonstrating the good level of reproducibility obtainable in operating the equipment.

Jan 1, 2000

By Totterdell JM

The Permian-Triassic Bowen Basin and the Jurassic-Cretaceous Surat Basin evolved in a backarc tectonic setting behind an active convergent plate margin in eastern Gondwana. Several extensional (Early Permian; Eocene) and contractional (mid- Permian; Early Triassic; Middle-Late Triassic; early Late Cretaceous) intraplate deformational events are recognised in the basins. These can be correlated with similar events in the New England Orogen that was being deformed in the Late Permian- Late Triassic as a foreland thrust belt. The intraplate deformations were probably the consequence of plate interactions, including the accretion of terranes, at the ancient active plate margin, remnants of which now occur in New Zealand.

Jan 1, 1995

By Rieniets S, Somerville J. L

In Morwell Open Cut brown coal mine, the overburden 'firehole' materials which have resulted from ancient coal fires vary-from hard baked clays to firm laminated lacustrine clays. The need to pre-strip designated areas to reduce the slope height and attain safe digging conditions for the bucket wheel excavator operation is now accepted practice at the open cut mine. In this study, the inherent spatial variability of undrained shear strength of the clay materials has been incorporated in a visco plastic, finite element based, probabilistic slope stability analysis. Data on the costs of initial pre-stripping, excavation and slope failure are collected to provide an economic basis for the optimisation of the design of the overburden batters in Morwell Open Cut. This improved stability modelling is enabling costly pre-stripping to be minimised while ensuring acceptable slope stability conditions and minimising the risk to personnel and plant.

Jan 1, 1994

By Andrews JRG

Chrysotile asbestos is a valuable resource. Used as a reinforcement in asbestos cement, products are obtained which are cheap, are not attacked by vermin, do not rot or support growth of fungi and are unaffected by water or humid conditions. Such products are of great value in the developing countries where inexpensive and durable building materials and pressure pipe are very important to development, housing and water supplies. Concern over the adverse effects of inhaling asbestos has led to the introduction of increasingly stringent controls world wide on the quantities of airborne asbestos per- missible in the occupational situation. Wet processing has the potential for virtually eliminating the environmental concerns with asbestos dust both in fibre production and in the materials handling section of the manufac- ture of asbestos cement products. In addition, high efficiencies associated with wet process- ing mean that better yields are obtained and that the tailings which are dumped have a lower residual asbestos content. Since early 1977, ICI Australia and Woodsreef Mines have been engaged in a programme of research to develop and evaluate a wet mill- ingprocess to produce, from ore and existing tailings, high grade fibre suitable for use in asbestos cement products. The process has been developed through microscopic studies, labora- tory bench scale experiments, work in a small scale semi-continuous plant and product evalua- tion on experimental size Hatschek asbestos cement machines. A prototype mill with a normal feed rate of 1z tonnes per hour and capable of producing pipe grade asbestos from Woodsreef ore has been constructed and was operational from January, 1982 to July, 1983. A range of asbestos cement products have been made successfully on full scale Hatschek machines using fibre from ore and tailings milled in the prototype mill. Economic evaluations indicate that a wet process mill would be cheaper to build, operate and maintain than an equivalent dry process plant. A commercial plant has been designed 1. Manager New Process Development, Woodsreef Mines Limited, Barraba, Australia. 2. Senior Lecturer, Department of Chemical Engineering, Monash University, Vic, Australia. formerly Senior Research Officer, Research Department, ICI Australia Limited

Jan 1, 1986

By J C. Macintosh

Capcoal Mine has modified its water use practices over the past 15 years. Two issues have changed the way water was managed:an economic review of water supply options for a planned expansion of the coal handling and preparation plant (CHPP) in the early 1990s, and increasing neighbour concerns about discharge of worked water from the mine into the local streams. These issues resulted in commitment by the site General Manager to cease discharge of worked water from site and to convert from using raw water to worked water in the CHPP. Operational needs, societal demands and continuing dry weather are again demanding change to the siteÆs water management strategy. This paper outlines the drivers for past and future operational change.

Jan 1, 2006

The Olympic Dam Mine is a large, mechanised, underground operation currently producing 2.2 million tonnes-per-year of copper/uranium/gold ore. The mine is accessed via one shaft and one service decline. An additional 13 raise bored ventilation shafts have been completed to-date.Ventilation requirements are stringent in order to provide adequate dilution and removal of diesel fumes, radon gas/daughters and heat generated from both engines and wall rock.Due to the nature of the orebodies, the mine workings will continue to expand laterally necessitating the addition of at least one major surface raise every year.

Jan 1, 1992

By Giannini LM, Carras S

A fundamental problem in mine planning is that of determining the "optimum pit limit" of a mine. This optimum pit limit yields information which is considered essential in the evaluation of the economic potential of a mineral deposit, and in the formulation of long -, intermediate -, and short-range mine plans. Since the mid 1960's a number of mathematical techniques based on the "block model" have been proposed for solving this problem. When applied to large ore-bodies the implementation of these techniques, especially the more elaborate ones, poses considerable computational problems. In this paper we report on our work, done jointly with Systems Research Institute of Australia (SRIA), in devising strategies for overcoming these Problems.

Jan 1, 1986

Refractory gold concentrates and their roasted products have been examined by mineralogical and chemical methods, and the distribution of gold in the tailings after leaching has been Investigated.

Jan 1, 1989

By B R. Bittencourt, D A. B Pasin, D Pi

Three main genetic types of hematite can be recognised at Quadrilßtero Ferrffero (QF): Micaceous or schistose hematite derived by metamorphic/metasomatic process during regional metamorphism, increasing eastward, formed under temperatures ranging from 250¦C to 500¦C in CO2-rich aqueous carbonic, high- to medium-salinity fluids. Hematite in shear and mylonite zones, showing a wide variation of fluid and temperature conditions, between metamorphic and hydrothermal conditions. Deformed quartz-specular hematite veins formed during the late phases. Hydrothermal, compact and isotropic hematite developed during a brittle-ductile regime, forming the cement of the boudinage-kink breccia and jacutinga-type of gold mineralisation, under temperatures ranging from 80¦C to 140¦C in aqueous, low- to medium salinity, oxidant fluids, resulting from the interaction of meteoric and metamorphic/metasomatic fluids. Quartz-carbonate-sulfide veins were formed slightly later, through reducing fluids.

Jan 1, 2005

By S F. Simmons, A McOnie, J L. Mauk

Three cross sections, 200 m apart, display the distribution of indicator hydrothermal minerals across the Empire zone of the Golden Cross epithermal Au-Ag deposit, Waihi, New Zealand. These minerals are used to interpret the temperature and composition of hydrothermal fluids. The distribution of interstratified illite-montmorillonite and illite indicate that temperatures ranged from 140 to >220¦C, with temperatures above 220¦C predominating. The mineral assemblage of quartz-adularia-chlorite-illite-calcite-pyrite envelops the Empire vein system and stockwork, and reflects formation from an alkali chloride water whereas the mineral assemblage of replacement calcite-interstratified illite û montmorillonite-kaolinite forms a carapace and reflects formation from a CO2-rich steam-heated water. Alkali chloride waters appear responsible for the epithermal Au-Ag mineralisation.

Jan 1, 1995

By L Soares, W T. Hennies, F Fujimur

Barra Bonita reservoir, located in the Sao Paulo State, Brazil, has been mainly used for local navigation and electricity generation to supply a prosper region in the country. Sand mining activities in that area have an important social and economic meaning for the local community. In this reservoir there are several sand mines that produce around 45 000 m3 of sand a month. These deposits were rich in material used as concrete aggregate in the civil construction. However, nowadays a significant increase in the demand of gravel can be observed, representing a serious productive problem. This material hasnÆt been well accepted by the market and, through the years, it was disposed at open sky in piles as waste deposits. This deposits have caused environmental problems like visual impact, reduction of free spaces outside and inside the mine, source of material to erosion and sedimentation processes in lower areas, flooding as a result of the filling up process in the drainage system, among others. For a lack of an appropriate technological characterisation, this material have been mainly used to pavement internal and external areas in the mine, with lower cost associated. With the purpose of evaluate the usefulness of this material in the conventional concrete, there were conducted several tests in the disposed residue including petrographical, physical, and chemical characterisation. The petrographical analysis and the preliminary results of the study showed that the material reacts with the alkalis that are present in the conventional cement (CP-II-E-32). In order to make the application technical and economically possible a research was developed seeking forms to correct this characteristic by adding special cements with high pozzolana content. The results of the technological, physical and chemical characterisation of the products indicated the technical viability of the use of that material. The study also allowed projecting environmental improvements resulting in the elimination of the waste piles.

Jan 1, 2003

By Grace B, Cunningham D

The poor quality of bore waters available to the Australian mineral processing industry creates a climate for crystallization of calcium based scales. If ignored, calcite and/or gypsum buildup can cause loss of production and costly unscheduled maintenance. This paper discusses the factors which contribute to scale forma- tion, methods used to monitor buildup and preventative measures (mechanical and chemical) that can be used. A case history il- lustrates the value of using chemical antiscalants.

Jan 1, 1991

Geostatistical conditional simulation is a method to assess variability and risk in mineral deposits and the tool has wide potential applications in the iron ore industry. Correct reproduction of multivariate relationships is important in iron ore simulation, especially between Fe and impurities such as Al2O3, SiO2 and P. The turning bands simulation method, using a full model of coregionalisation for multiple attributes, is the main multivariate conditional simulation algorithm used in the Western Australian iron ore industry. This paper discusses the results of a more recent approach using minimum/maximum autocorrelation factors (MAF) to transform and decorrelate the multivariate data prior to independent sequential Gaussian simulation (SGS). MAF-SGS results are compared to those of the turning bands approach in the Yandicoogina channel iron ore deposit (CID), and both methods performed well in simulating Fe, SiO2, Al2O3 and P distributions. Extensive checking of simulations showed that both approaches could reproduce multivariate statistics and spatial continuity of the original conditioning data. Both approaches reproduced the histograms and variography of input sample composites. While the MAF-SGS approach requires additional transformations when compared with the single normal scores transformation required for the turning bands method, MAF requires only that the direct semivariograms be modelled. In contrast, using turning bands with multiple attributes requires modelling a full linear model of coregionalisation, which can be difficult to model because of the need to ensure the model is positive semi-definite. Turning bands may be preferred if there are a modest number of correlated variables allowing construction of a linear model of coregionalisation that adequately models the multivariate behaviour. MAF-SGS is preferable for larger numbers of correlated variables. Both MAF-SGS and turning bands methods performed well in conditional simulation of correlated variables at Yandicoogina.

Jan 1, 2007

By Shining Z

The properties of coal or rock containing gas are very important both for studying coal and methane outburst mechanism and for controlling underground rock in mining. The rheological fracture properties of coal containing gas were studied to obtain its rheological fracture principle both in microscopic scale and in macroscopic scale. The application of this principle is successful in explaining coal and methane outburst mechanism and for putting forward a rheological hypothesis of coal and methane outburst.

Jan 1, 1992

By Anderson KG

Multi-seam mining under the western portion of Lake Macquarie NSW commenced in 1982. Up to three seams separated by partings ranging from 10 to 30 metres are mined simultaneously by Newcom Collieries. A feature of these workings is the minimal bedrock cover, which ranges from 130 metres down to only 40 metres. "Surface" subsidence control has an over-riding influence on the design of the workings. Subsidence considerations govern both the selection of the mining method and the dimensioning of the workings. To date, workings have been designed in accordance with the "Wardell Guidelines for Mining Under Tidal Waters". These guidelines are tabulated and evaluated in the light of advances in rock mechanics knowledge and local subsidence data collected since the Guidelines were formulated in 1974. The local and regional stability of shallow workings designed according to the Guidelines is evaluated.

Jan 1, 1986

The design and construction of a 2.5 million tonne per annum ship unloading system at the PWCS export coal terminal in Newcastle, NSW, has further increased the flexibility and sophistication of Australia's largest coal export facility. The system comprises a new unloading wharf serviced by a self unloading vessel, conveyor stream and multi compartment ground level storage shed. Coal is reclaimed from this shed by the largest portal scraper ever installed under cover. The system also provides additional flexibility by receiving coal from the existing PWCS road receival to improve scheduling. The PWCS can now simultaneously handle 11 coal types and receive from rail, road and sea at almost 15000 tonnes per hour.

Jan 1, 1987

Silver-lead mineralization at Indooroopilly, Queensland, extends upwards from Upper Triassic rhyolite which intrudes phyllite-containing Palaeozoic mineralization.Sulphides and magma were emplaced in a special structural site which underwent dilational fracturing while surrounding rocks were block-faulted and compressed. This site lies at tbe intersection of dykes, faults, and a lineament adjacent to a Middle Triassic granitic stock.Structural controls at Indooroopilly are attributed to the effects of piston faulting. Exploration for similarly controlled deposits should be directed towards structural intersections near stocks or batholiths which have intruded mineralized belts. Priority should be given to structural intersections which were sites of block-faulting and igneous activity under compressional tectonic conditions.Favourable sites lacking surface mineralization may contain ore at depth as piston faulting produces 'blind' ore deposits.

Jan 1, 1976

By Phillips H. R

The action of free rolling disc cutters is well understood, relationships between disc geometry and performance having been established both in the laboratory and under field conditions. However, under severe operational conditions a malfunction of the disc bearing assembly is likely to produce a definite change of cutting action. Collapsed or siezed bearings can even prevent the disc from rolling and thereby create what is equivalent to a drag pick. This paper describes a programme of laboratory experiments using deliberately stalled discs. Their performance under such conditions is contrasted with that for a free rolling disc and also with a drag pick having a ridged front developing into a negative radiused back clearance angle. In conclusion an assessment is made of the influence stalled discs can have on the torque and thrust requirements for a tunnel boring machine.

Jan 1, 1981

Tokyo Metropolitan Government designs the stormwater storage plans in underground, as a measure of flood control in completed urban district and improvement of combined sewarage system. This time, introducing those plans, we report about IKEJIRI and SIN-KOMAZAWA STORAGE TRUNK LINEs design and construction. They are located in Meguro river basin of the Morigasaki drainage area. Both storage trunk lines have capacity to store 15O,000m3 of stormwater. They are in use for countermeasure of flood till Meguro river's strengthening (intensity 50 mm/h) is ended. And after the strengthening, they will be in use for improvement of river water quality, through the storage of combined sewage and first runoff, which, otherwise overflows weirs and flows to river in a rainy day. These storage trunk line's full length is about 5700m. Boring diameter 66140 mm (f = 2672m) and 47800 mm (I = 2866m) of these tunnels are constructed by Mechanical Shield tunnelling method. And boring diameter 3600 mm x 4000 mm (R = 180m) is constructed by NATM tunnelling method. We began works in 1983, and have a mind to complete in 1987.

Jan 1, 1987