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By Rawlings C. D

An assessment is made of the potential for thick seam underground mining of black coal in Australia. A brief summary is given of the geomechanical environment and previous mining history existing in a number of areas of particular interest from the point of view of thick seam mining. A classification of thick seam mining methods is presented with emphasis on the critical geomechanical para- meters influencing the performance of such methods. A summary is made of perceived geomechanical research requirements related to thick seam mining in Australian coalfields.

Jan 1, 1980

Fluid bed sulphation roasting of bismuth concentrates began at Warrego in 1980 in con- junction with the recommissioning of the Tennant Creek Smelter. This process, develop- ed by Peko Mines, is used to separate copper and bismuth by converting copper minerals to a water or weak acid soluble form and then leaching. Pilot scale testwork conducted at the Australian Mineral Development Laboratories (AMDEL) and by Dorr Oliver Pty Ltd in the USA indicated that close control of bed teaper- atures and exhaust gas composition was required to ensure high levels of soluble copper. After overcoming some initial problems, the plant now achieves typically 89 percent copper extraction. Plant capacity is 2.7 tonnes/h by design but in practice this is limited by feed analysis, air requirements, cyclone operation and calcine particle size Consideration.

Jan 1, 1984

THE Taranaki oil-field is situated on the western side of the North Island of New Zealand, at about its widest part, and may be said to be the most compact and fertile part of the Dominion, for, with the exception of the. upper half of Mount Egmont and of the ranges adjoining, which absorb 36,000 acres, the whole of the area, miuus what is taken up by the rivers land streams-is suitable for settlement, and certainly two-thirds is good land. The gross area oE the district is 2,417,299 acres.The principle rivers are the Wanganui, Mokau, Waitara, Patea, and Waiwakaiho. Mount Egmont, which is 8260 ft. high, used to be called Taranaki, and from it the district takes its name (the Maori meaning of which is "sloping peak ").

Jan 1, 1911

Coal exports are forecast to grow strongly, so that coal is likely to remain very important to Australia for the foreseeable future. However there is no sign that prices or profitability will rise of their own accord. Therefore the intense squeeze on costs will continue for the foreseeable future. This will mean lower manning, more outsourcing and probably an increasing rate of company attrition. As well, the political pressure from the greenhouse debate is only going to intensify and the pressure on the Federal Government after Kyoto is likely to be irresistible.

Jan 1, 1998

By Grinbaum B, Stevens G. W, Dalton R. F

Many hydrometallurgical processes produce large amounts of acid waste. This is illustrated by the copper S/X-E/W process which produces a bleed from the electrolysis tank house in the form of a concentrated sulphuric acid stream. Currently, the bleed stream is necessary to remove impurities such as iron that decreases the efficiency of the electrowinning process. However, this comes at a high financial cost owing to large quantities of make-up sulphuric acid required. A process has thus been developed with Zeneca Specialties (UK), ICI Australia and Gunpowder Copper Co at the University of Melbourne for the recovery of sulphuric acid from copper tank house bleed liquor. The recovery process uses the method of solvent extraction. Solvent extraction has the advantage of being a well-established technology in the mining industry and will reduce the environmental impact of the S/X-E/W process, as all additional chemicals can be completely recycled. A simplified diagram of the process is shown in Figure 1. Tank House

Jan 1, 1997

Aberfoyle sought to reduce Hellyer project development risk to a greater degree than usual. Consequently the ore reserves estimate and feasibility study were particularly comprehensive. A detailed ore reserve study was completed based on extensive drill core and underground sampling, large scale pilot plant work and a detailed feasibility study. Leading external consultants were used for advice on commercial matters which impact on ore reserves and to audit major technical conclusions, including the results from pilot plant work and the ore reserve estimate. Other project risks were diminished by negotiating a State agreement covering security of title, royalty formula and environmental management procedures, by obtaining sales contracts, and by analysing Hellyer's position on an industry cost curve. The task of financing the project was much simplified by the extent and quality of information available from the ore reserves estimate and feasibility study report.

Jan 1, 1990

By Watkins JR

The educational system is a dynamic; a flow resource that can be significantly shaped, changed and - refined by educationists. This paper analyses these various facets of geo- science education in Australia. The Australian educational philosophy is essentially a laissez- faire model, a free market approach without any real government or professional directive or stratagem. Students are therefore free to choose their own educational pathway dependent only upon their ability and the access to courses. Geological education at the tertiary level in Australia is described and critically analysed. There is a real need for a rationalisation of geological education in Australia, and this rationalisation should include not only the number of courses offered but should also aim to fully define both the philosophy and purpose of geological education and the accreditation procedures for the Students.

Jan 1, 1986

By Cecala AB

For 20 years the US Bureau of Mines has been researching strategies for improving the physical, social, and psychological work environment of the miner. The products of this program have shown that a consistent link exists between safety and productivity, and the key to this link is the use of effective human factors and management practices. There are specific research findings from the research projects of the Bureau on ergonomic design of mining equipment, redesign of tasks (especially materials handling) to minimize back injuries, human resource management techniques for increasing safety and productivity, and improved shift rotation schedules. Current research is continuing these themes with new applications to high technology mining systems, including computer assisted extraction devices and mine monitoring.

Jan 1, 1991

The primary objective of any planning exercise is to maximise the return on funds utilised while maintaining a safe and socially responsible working environment. In order to achieve this, it is essential that the assumptions applied reflect as accurately as possible the future realisation of the project. In narrow vein mining, the risk that this will not occur can be significantly greater than that associated with other types of mining projects. This results partially because of dramatic effects upon project cash flows with seemingly minor changes in operating parameters such as orebody width and wall rock competency.The validity of a planning exercise can therefore be related to the extent of available data and to the experience and perceptions of the operating entity. The various factors which must be assessed include absolute values and variations in a range of factors, especially the dip and dimensions of the orebody, the geotechnical parameters and anticipated ground conditions, the productivity and production characteristics of the selected mining method as applied to the specific orebody, and the impact of mine access and development.

Jan 1, 1993

By W A. Tchernykh, R P. Strelnikova

In connection with the fact that technology of ore mining by caving system is often used when mining of deposits, characterising by low stability of surrounding rock mass, the main problem for such ore mines is ensuring stability of mine workings, placing in a zone of influence of winning operations. Besides natural disturbance of ore mass, stability of workings depends on the dynamic effect of blasting operations and also on the dynamic effect of structural blocks detaching from the ore mass and colliding with crests of ore pillars in the bottom of a chamber. Decreasing of dynamic stresses may be achieved by way of creation of a compliant porous screen or an ore cushion in the chamber bottom. It is established that maximum levels of compression take place when the first impact impulse occurs, and after that increase of compression of protective slice decreases. Necessary thickness of screen slice was substantiated theoretically with due account of height of structural blocksÆ fall, their mass, deformation modulus of ore mass and ore cushion.

Jan 1, 2003

By Enichlmayr E

Lignin grouts are cheap and easy to get. They have some desirable properties, but they aag less used now because environmental pollution is often caused by Cr from the lignochrome component of the grout. Their usefulness was researched in an earlier paper on lignin as a grout from other viewpoints. A non-toxic grout FUL was made composed of furfural, urea and lignin. After initial tests, including tests by spinning regression design, some response equations in which FUL's properties are described were obtained. Optimum formulations have been established by using optimization methods based on response equations. The engineering quality was assured by formulations whose properties were measured in further tests. The mechanical feature of gelling sand was measured by means of triaxial tests. This provides a basis for using FUL grout in-situ. Finally, an in-situ experiment on FUL was completed successfully. The results were that cracks in stratum were filled or blocked, the gelling of FUL had high strength, and low permeability and consolidation were achieved.

Jan 1, 1988

A Master of Applied Science degree course in Mining Geomechanics commenced in 1983 at The University of New South Wales, taught by extern- al (correspondence) studies. The course is aimed at graduates employed in the mining indust- ry, and especially people involved in geomechan- ics projects on a routine basis in remote locations. This kind of course is unique in Australia and is one of only two correspondence programmes available at this University. The author designed the course and nursed it through the early years, and was Director until 1986. The paper describes the teaching and assess- ment methods and also discusses aspects of admin- istration and coordination of such a course. It is concluded that an important need of the mining industry is being catered for and it appears that similar correspondence course for- mats would also be useful in other areas of the minerals industry.

Jan 1, 1986

In China the hydrogeological type of solid mineral deposits can be divided into A. Mineral deposits with fissure water; B. Mineral deposits with pore water; and C. Mineral deposits with karst water. The hydrogeological conditions of mineral deposits with fissure water are relatively simple with the exception of a few cases. Mineral deposits with pore water are few but great amounts of ground water can be encountered in the mine accompanied by floating sand or slope failure during the exploitation. Mineral deposits with karst water are complex in their hydrogeological conditions. Enormous inrushes occur frequently in the mines of north China; Karst collapses are a serious matter in the mines of the south; Subterranean river and conduit systems are often encountered in the southwest. This paper will give full discussion on these features and put forward a way of combating and controlling the groundwater problem in accordance with type and feature.

Jan 1, 1988

By Mason P, Waller C

The Phase I electrowinning system at KCGM's Fimiston Operation utilised the well proven technology of electrowinning precious metal values onto steel wool followed by calcining and direct smelting to bullion. The above process, while reliable and successful, was to some extent labour intensive. The Williams Mine in Ontario, Canada had published conditions under which precious metal values are electrowon onto woven stainless steel and directly removed using high pressure sprays. The current paper describes the testwork which was carried out to check the applicability of the Williams criteria to KCGM eluates arising from the elution of highly loaded carbon from the calcine circuit and lowly loaded carbon from the float tails circuit. Information is also given on the commissioning and operational experience which occurred.

Jan 1, 1996

The concentrated efforts now being directed towards the development and application of monitoring and control techniques have now resulted in their widespread use in UK mines together with evidence of benefits resulting from their application. There is little doubt that the longwall method of producing deep mined coal will continue but will be made more reliable and efficient with the aid of control technology. The major fields of research and development work are concerned with planning and design of mines and mining equipment; management and engineering information; and automation of coalface, tunnelling and transport systems. The principal achievements now in widespread use are: the standard computer system MINOS, widely applied to mine transport, coalfaces and mine environment; extensive use of machine condition monitoring leading to condition-based maintenance; underground automation of conveyor systems and guidance systems for ranging drum shearers and boom-type roadheaders are being widely introduced.

Jan 1, 1985

Field investigation of surface subsidence events associated with both active and abandoned underground coal mines in the United States has established criteria that enable the prediction and classification of mine-related subsidence. The key was establishing the role of geology in all types of subsidence and the recognition of beam subsidence in specific geologic settings. The classification is based on overburden thickness, variations in stratigraphy, topography and mine plan. Types of subsidence are Pit, Room, Sag, and Beam. Pit subsidence is associated with three geologic settings: shale overburden, seasonally wet unconsolidated overburden, and perched water table in unconsolidated overburden. Room subsidence occurs where the roof across the width of the room fails to the surface and a shallow depression develops.

Jan 1, 1992

The strategy of adjusting operating conditions to maintain optimum process performance as the feed quality varies - adaptive optimisation - is being investigated by computer simulation of chemical processes for the treatment of ores. Those ore-process systems that are most likely to yield substantial benefits from adaptive optimisation are being identified as a guide to the selection and development of systems for practical application. The generalised mathematical representation of the cost structure, ore quality variations, process kinetics, reactor characteristics and operating variables for ore-process systems is described. Results are summarised for temperature, reagent concentration or residence time as the manipulated variable. For almost all systems, adaptive optimisation was economically beneficial, although a few exceptions have been identified where there is a significant synergistic effect between poor-performance and good-performance materials in a blended feed. The sensitivity of the benefits of adaptive optimisation to a range of economic and technical factors is summarised.

Jan 1, 1985

In Europe there are many regions, where coal or lignite is mined with surface methods. In most of these regions coal/ lignite is mined below groundwater table and mining opera- tions require pumping big volumes of water. Drawdown of groundwater table has influence on surface water and ground- water on adjacent areas. Mine drainage requires purification and its discharge changes flow in existing streams. Some of mine water is used by mining companies themselves, some is used by other industries, some for communal purposes and some for irrigation. However, majority of mine water is dis- charged to rivers without use. The above issues are discus- sed on the background of general, technical and water charac- teristics of such regions in B European countries. Conclu- sions and prospects for future complete the paper.

Jan 1, 1988

A number of small copper deposits occur in the Pernatty Lagoon-Mt. Gunson area. Textural and mineralogical differences distinguished the lagoon sulphide deposits, which occur in a water filled basin of permeable bedrock immediately under the lagoon floor, from the largely oxidized deposits which occur in the low hills adjacent to the lagoon deposits.Groundwaters are carrying copper, and to a lesser extent zinc, downstream to the lagoon. Several species of sulphate-reducing bacteria are widespread in the groundwaters and lagoon muds.It is suggested that copper sulphides were first deposited at the same time as, or soon after, the host Proterozoic sediments, and that during the present cycle of erosion the lagoon deposits may have been enriched, or largely formed, by bacterial precipitation of copper sulphides from laterally migrating cupriferous groundwaters.

Jan 1, 1971

Equilibrium in the reaction H2(g) + [%0] (in liquid copper) = H2O (g) was investigated at temperatures between 1200 -and 1350°C with p(H2Oj/p(H2) ratios between 1 to 15. A semi-microbalance was used for direct measurement of dissolved oxygen in molten copper. Oxygen was found to obey Henry's law under the experimental conditions used. The standard free-energy change for the above reaction is given by Equation 1where 1 weight per cent solution is the standard state for dissolved oxygen.For the dissolution of oxygen in copper according to 1/2 O2(g) = [%0] (liq. Cu), the standard free energychange is given byEquation 2.

Jan 1, 1973