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After a very brief historical survey and overall assessment of traffic requirements, the invitation by the British and French Governments for private groups to make proposals for a "fixed link" is described, and the resulting plethora of proposals is reviewed. The three schemes which gave some promise of being adequately backed by private finance are described as follows:

Jan 1, 1987

By D G. Miljak, J Khachan, B K. Schwitter

The performance of prototype magnetic resonance sensors suited to mineral measurement in conveyor, slurry or portable applications is described. The sensors can be positioned around conveyors and modified slurry pipes, providing deep penetration of the sensing field, relative insensitivity to ore surface conditions and high mineral discrimination. Measurements on slurry, concentrates and ores sourced from mine operations are presented for two applications. Firstly, the quantitative measurement of chalcopyrite in slurry was demonstrated in laboratory measurements. In a calibration test, a standard error of 0.1 wt per cent and detection limit of 0.3 wt per cent was obtained. Secondly, results were obtained for the discrimination of iron ore texture. Signals were readily observed using measurement integration times of seconds to several minutes, depending on ore material. The results demonstrate the feasibility of online quantitative analysis of selected minerals in processing applications using magnetic resonance.

Jan 1, 2008

By Kerr M. H, Slaughter P. J

Design of the new cemented hydraulic fill plant was based mainly on experience with a succession of previous fill plants. Two stage cycloning of combined concentrator tailings was introduced. Design of the two stage cyclone configuration was assisted by computer simulation of cyclone performance. Cementing additives, namely Portland cement and ground copper reverberatory furnace slag, drawn from bulk storage, are pre-slurried prior to mixing with hydraulic fill. Quality control of fill being sent under- ground is achieved by a series of automatic control loops. Plant instrumentation was given prime consideration during the design phase. Inventory checks of all mass flow metering equipment are made at regular intervals. Fill is pumped to boreholes at several locations. Details of the equipment and operating procedures for the plant are Discussed.

Jan 1, 1973

By Sinha NH

ICI Australia and CSIRO have developed a novel process for extraction of zirconia from zircon sands. The two stage process involves a high temperature step and a wet chemical processing step. A pilot plant has been operating since November 1985 at CSIRO Division of Mineral Chemistry, Port Melbourne and construction of a full scale plant isplanned at Kwinana, WA.The plant has a high degree of flexibility and is capable of producing high purity zirconia up to about 99.99% and withinspecific particle size ranges. The products are being marketed by the joint company, 2-TECH Pty Ltd.

Jan 1, 1986

By Kohra A, Shoji S

The amount of copper production by flash smelting process occupies about 17% (equivalent to 1.4 million t/year) of total free world production. In Japan, 650,000 tons of copper is produced annually by flash smelting. This is 65% of the gross copper production of Japan. To reinforce pollution control, promote energy saving, and enhance production efficiency by increasing the size of furnaces, conventional blast furnaces and reverberatory furnaces are being replaced with the flash smelters worldwide. The Ashio Smelter started copper production in 1884 and developed in association with the Ashio mine. In those days, the Ashio smelter produced copper by using the blast furnace process designed for the high-grade ore from the copper mine. At that time, this process was specialized in Japan. In 1956, for the first time in Japan, the Ashio Smelter introduced the flash smelting process developed by Outokumpu Oy of Finland (it is suitable for treating the copper concentrate, producing sulfuric acid and improving production efficiency). The flash furnace in Ashio, the first ever in Japan, had a capacity of 230 t/day for copper concentrate and was operated up to 1962. During this period, various operational troubles were solved, and further improvements were made; and, in 1962, a Furukawa-type flash smelting furnace was completed in Ashio. This improved version of a flash furnace had a capacity of 450 t/day. There was one flash furnace and one waste heat boiler, which were arranged in a unique pattern for that time. This furnace may be said to be the prototype of the present flash smelting process in the world.

Jan 1, 1987

The process and control technologies incorporated into the coal preparation plant at Newlands were to be used for the first time in Australia. The commissioning organisation and procedures were set up on the basis that commissioning personnel, while being competent, would be unfamiliar with the equipment. In addition the commissioning process would have to be completed quickly. The organisation coped with all of these problems and more.

Jan 1, 1986

When a thin film of volatile matter is deposited under vacuum on a polished coal surface, and the coated surface is examined microscopically in piano--polarized reflected light, colour changes are observed characteristic of the various macerals present. The colour changes appear to be mainly due to interference between light reflected at the upper surface of the film and at the film/coal interface. A variety of source materials for the volatile matter required have been tested, including powdered bituminous coal, coal tars, boron oxide, and certain resins.

Jan 1, 1969

By Sinha DK

Coal Mining in India had been confined in the past primarily to two or three coalfields. Unscientific mining has led to huge degradation of land including massive subsidence of strata and disturbances of water tables to a wide extent. This has caused problems not only in flooding of mines from surface water but also in further planning of the surface drainage for current mining activities. Now, therefore, surface hydrology and land-use potentialities of the area have been endangered inflicting severe damage to the overall environment and ecology of the area. The paper Discusses certain investigative aspects of the problems highlighted as above in one of the coalfields, and encompasses mainly the following areas : 1) Quantitative estimation of the damage already done to the natural surface drainage system. For this purpose damage to topography and drainage for the last fifty years have been made out through the aerial photographs and topographic map sheets 2) Analysis and comparison of different states of such photographs are carried through to indicate the extent of damage to the hydrological conditions inducing undesirable changes in its land-use pattern. Based on the analysis, concrete suggestions are made to restore the water drainage system which will be most suitable for future mining in the area containing high grade coal. The design and planning of the drainage system is based on the total system approach including the cost benefit analysis as well as hydrological considerations.

Jan 1, 1988

Prior to 1980 the thought of the occurrence of high-level epithermal gold mineralisation occurring in eastern Queensland would have been more of a dream than a reality. In a world-wide sense the understanding of the processes and tectonic settings for epithermal gold were only beginning to be developed. Although epithermal gold deposits had been mined in the past in Queensland the significance of these deposits in a regional sense had not been appreciated. A number of companies had made cursory examinations of epithermal regions in the Mt Coolon and Cracow regions. Since the mid 1980's the search for epithermal gold mineralization in Queensland was truly on and over 30 tonnes of gold from this style of deposit has been discovered.

Jan 1, 1989

By Fisher AEJ

On Sunday morning 7th November, 1976, at approximately 2-25 a.m., smoke was discovered issuing from the 1912 m long belt drift at Appin Colliery. A Clouth steel cord rubber belt approximately 940 mm in width had been installed in the drift in 1963 on the basis that no fire resistant steel cord belt was then available to operate on a single lift at the load and on the 160 gradient of the drift. Investigation showed that the belt drift was on fire and the usually downcasting drift was upcasting. Immediate fire fighting and rescue operations were instituted and the drift was sealed off. High expansion foam was pushed into the drift from the surface and the fire was brought under control. Recovery work resulted in the fire being put out and the drift open for walking traffic by, S-P0 am., on Wednesday 10th November, 1976. lie experience gained during the fire fighting and recovery operations led to recommendations in regard to future use of high expansion foam.

Jan 1, 1981

The proportion of coal production from underground operations in Queensland, is likely to increase in the future. A portion of this increase will come from mines working under farming areas. The degree of compatibility between underground coal mining operations and farming is examined. Two case histories are considered in detail. These relate to farming areas in the Moura and Emerald districts. Mining the Moura, area has been undertaken for the last two and half decades, while in the Emerald area, large scale underground coal mining is currently being planned. Interference to watercourses and water harvesting programmes, damage to crops, and ponding in cultivated areas have been experienced in mining areas. With expansion of underground mining in farming areas, the principle areas of likely conflict are the effects of surface subsidence on irrigation and erosion control structures. Other potential problems that may arise in particular circumstances include reduction in availability of water for harvesting, pollution, surface cracking and damage to surface structures. Finely textured soils and erratic and violent rainfall patterns make farming in central Queensland particularly vulnerable to severe soil erosion unless strict precautions are taken. Soil erosion control is an essential part of farming. Contour banks are used to ensure that runoff velocities are suitably low. Where steep slopes are encountered, grassing is the most effective way to prevent erosion.

Jan 1, 1987

By Y Wei, H-B Mnhlhaus

Particles are by far the easiest objects to simulate, because their dynamics is simple. Determining the motion of particles and their interaction, a wide variety of deformable structures can be constructed by connecting particles that have mass, position, and velocity, and that respond to forces. Starting from this simple idea we have derived what we call the particle-lattice method for the solutions of boundary value problems of deformation and fracture of solid mass. The problem of rock breaking by blasting operations as well as fracture and flow of rocks fragments involve momentum transfer between solid and fluid; gas flow and reactive mass transfer. In this paper we outline the method and describe briefly the salient features of the algorithm. We derive relationships between the contact properties for the discrete model and the properties of the underlying continuum and fluid flow coupling procedure. Finally we illustrate the potential of the method by means of example solutions related to the dynamic fracture and flow in jointed rock by blasting.

Jan 1, 1999

Copper entering a lead ,smelter in concentrate or from other sources is recoVered as matte and speiss which contain appreciable quantities of lead. The matte and speiss are usually sold to copper smelters to recover the copper content and also any gold and silver in these products, but the value of the lead is largely lost. Some copper plants pay for portion of the lead content, but regarded as a means of recovering lead it is more costly and less efficient than if the lead were recovered at the lead smelter.Because of the value of this lead loss, the metallurgy of copper recovery has assumed greater importance in recent years owing to the rise on the price of lead.Two processes are in use today to produce matte and speiss, namely the iron matte process and the soda matte process developed by the American Smelting and Refining Co. 1 in D.S.A. The latter process is characterised by a higher copper to lead ratio than the older iron matting process.The following analyses are typical of matte and speiss produced at Broken Hill Associated Smelters, by both processes, although the soda matte process is still in a developmental stage and experience indicates that matte and speiss of lower lead tenor can be produced under favourable conditions.

Jan 1, 1951

Feasibility studies in the development of mining projects are fundamental to most investment decisions. It is important that the issues addressed and the degree of detail involved in feasibility studies are consistent with the investment decisions to be taken. Emphasis should be placed on a thorough analysis of critical project parameters prior to detailed investigations being undertaken into other activities which are not relevant to the decisions at hand. Therefore, the issues to be decided upon should be influenced significantly by the stage of development of the project and by the reliability of technical and financial information used in the study. Some of the more critical parameters of feasibility studies are commodity prices, inflation rates and discount rates. Advice is given on the selection of these inputs and also on their application in the feasibility study as the project progresses through its various development stages. The feasibility study should involve not only a formal evaluation of project economics but also an analysis of all project related risks and a comparative analysis of projects competing in

Jan 1, 1983

The paper discusses the characteristics of Be-zymianny activity during the last 2500 years. Three periods of increased activity have been identified which are the eruptive cycles lasting for 100-400 yrs. The periods of high activity fall on the fol-lowing time intervals: 2400-1700 yrs ago, 1350-1000 yrs ago and from 1955 ixp to the present time. The 1955-1956 catastrophic eruption after a long period of repose (about 900-1000 yrs) opened a new cycle of activity of the volcano which is continuing to-day. Several decades are distinguished in activity which differ in character and intensity of eruptions.

Jan 1, 1990

By Restarick CJ

Plant data are presented which indicate a relationship between flotation rate constants and pulp density in zinc cleaning circuits at Broken Hill. The data were obtained from down the bank sampling of cleaner and recleaner banks at North Broken Hill and New Broken Hill Consolidated Concentrators. It was found that, under normal plant operation, flotation rate constants increased at the lower pulp densities existing in the later cells of cleaner banks. The addition of dilution water to the feed to the bank increased flotation rate constants, thereby confirming the relationship. It is shown that the relationship between flotation rate constant and pulp density is size dependent, being most pronounced for larger sized particles. In contrast, the effect is not markedly dependent upon mineral type. Possible consequences of this relationship for control of cleaner operation are discussed with the aid of some simulated results.

Jan 1, 1978

The cost of constantly extending a decline tunnel that plays a part in the actual extractive process is a revenue cost. The characteristics of such a decline tunnel are that it is dug in a series of relatively small excavations. It follows the ore body and is dug as close to the ore body as practicable. In addition, the decline allows for the extraction of ore in the immediate vicinity, with the ore being extracted in a relatively short period of time.

Jan 1, 1990

By T A. Helms, P Gottlieb, S E, R Bateman

In response to the ever-increasing challenges facing the modern gold mining industry and the need for improved gold recoveries within all processing streams, CSIRO has upgraded its latest automated mineralogical analysis system, QemSCAN (formerly QEM*SEM), with special purpose hardware that speeds up the location and measurement of precious metal-bearing phases. By rapidly scanning the surface of polished blocks, and accepting only fields that contain the minerals of interest, QemSCAN is able to find, map, and quantify target minerals in extreme detail. Phase identification and quantification is achieved by placing a grid of points over the target particle and collecting X-ray information at each analysis point. The resulting mineral maps provide the metallurgist with a complete textural description of all gold-bearing phases within the product measured, together with quantification of the gold phases in terms of their modal abundance, particle size, mineral associations, relative contributions to gold deportment and liberation characteristics. Examples are presented which illustrate how QemSCAN is able to find and quantify gold-bearing phases within low-grade ores from the Super Pit, Kalgoorlie. This work is the result of a collaborative project between Kalgoorlie Consolidated Gold Mines (KCGM), CSIRO Minerals, and the University of Queensland, and is on-going.

Jan 1, 2000

By Johnston G, Revy T

Dominion Mining Ltd. and the JKMRC have conducted a detailed investigation of the performance of two of Dominion Mining's gold treatment plants (Haveluck and Paddy's Flat). In terms of design each plant is considerably different. The Paddy's Flat plant uses a single stage SAG mill with recycle crusher, followed by single stage ball milling. The Haveluck plant uses the more traditional approach of multi-stage crushing and ball milling. The performance of these two plant designs in terms of energy efficiency and cost of comminution equipment, developed at the JKMRC, to accurately predict both power draw and size reduction characteristics at these plants is evaluated.

Jan 1, 1991

By Cook B, Cunningham J

At Mount Isa Mines, a system has been developed for general monitoring of underground mobile equipment. It can provide unit condition monitoring data such as oil pressures and motor temperatures as well as production type information such as unit location and load. The system does not rely on an expensive data communications infrastructure, using instead inexpensive radio base stations which automatically transfer data from mobile units to a surface database server on the company-wide computer network. This paper includes a general overview of the system and a discussion of the practical benefits it is expected to generate.

Jan 1, 1995