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The problems of the as-built water supply system are discussed. Recent modifications to the collection dams and the water cleaning station using wedge wire screens to resolve these problems are outlined.

Jan 1, 1978

Grey River Gold Mining Ltd commenced dredging alluvial flats in the Grey River Valley in 1989.Previous drilling indicated over 100 million cubic metres of gravels with some 90% of the gold in the bottom 7 metres.The dredge built by Rahco, Spokane, was innovative in a number of aspects but particularly in the fact that a separate ladder with a cutter and pump was used to strip the overburden and a bucketline to mine the gold bearing wash below.Metallurgical studies and exploration were initiated when the project commenced; Leasing and environmental considerations were investigated and action taken.While progress is being made, the operation at this stage is not meeting required production and performance. Main problems have been with the stripping system and wear.

Jan 1, 1990

By Taylor R. N

Flow simulations have been performed on the flash-smelting burners currently used at KNS. This paper presents studies of the heat transfer between gas and particles at the burner exit. Gas and particle temperatures, velocity and concentration profiles of the two-phase flow are calculated by the mathematical model. The predicted gas temperatures have been favourably compared against values measured by thermocouples placed near the burners in the flash furnace. The predicted particle temperatures are also reasonable when compared with the measured temperatures.

Jan 1, 1992

By Webster SS

This paper uses computer modelling tech- niques to compare and contrast anomaly patterns obtained with fluxgate (vertical field) and proton precession (total field) magnetometers at typical latitudes in northern and southern Australia. The use of these modelling tech- niques is suggested as an aid to magnetic interpretation and field examples are included from Tasmania and the Northern Territory.

Jan 1, 1975

This paper reviews the issues of mining machinery automation with special emphasis on underground applications. Automation is desirable because it offers the following advantages: ò increased safety by reducing human exposure to hazards of underground mining; ò higher productivity; and ò reduced wear of equipment. In spite of these advantages and in spite of numerous attempts over the past several decades, mining automation has been a difficult proposition, partly because no two mining operations are exactly alike and these operations are carried out in an unpredictable environment. This is the main difference between automation in factories and in mines and that is why mining automation has been lagging so far behind factory automation. Automation is possible only when the machine 'knows' its workspace. In a factory, this workspace can be 'described' to the machine because it is sufficiently controlled. In a mine, the environment undergoes continuous change and the only way the machine can 'know' its workspace is through real-time sensing.

Jan 1, 1995

On Monday, October 25th, 1971 at approximately 12.15 a.m. the night shift proceeding underground discovered smoke at No.1 and No-3 cut throughs on the eastern side of the belt heading and in close proximity to the upcast shaft. Attempts to control the fire continued throughout the morning; as the position underground altered various procedures were adopted in an effort to contain and control the fire. Despite these efforts at approx. 12.40 p.m. a sudden change occurred which made it necessary to withdraw all workmen from underground, the vicinity of the Tunnel entrances and upcast shaft. Sealing of the mine at the entrances was the only remaining alternative. Several boreholes were put down to enable sampling of the atmosphere and air temperatures to be taken. This was essential as a guide to determining when conditions were suitable to allow exploration of the area using mine rescue self contained breathing apparatus.

Jan 1, 1972

Western Mining Corporation, managing partner of the Windarra Nickel Project are in- stalling a raise-bored haulage shaft and under- ground crushing system at the Mt. Windarra Nickel Mine. The system will be the second of its type installed by W.M.C., the first being in- stalled at the Otter-Juan mine in Kambalda in 1976/77. Both haulage systems became necessary as a result of the increasing production limi- tations, and escalating costs of a deep decline mine. The Windarra haulage system required a single 3m diameter vertical raise drill hole to a depth of 470 metres. Two five tonne skips in balance will hoist crushed ore and mullock to the surface, at a design rate of 200 tonnes per hour, effectively reducing truck haulage leads by up to 50%. It is expected the project will be in full operation by mid 1982 and will enable the mine to achieve an annual production rate of 600,000 t.p.a. by 1983.

Jan 1, 1982

Five types of mineral resource were known in the sedimentary cover of the oceans and seas floors prior to the 1980's :1) hydrocarbon fields including some very large zones of oil and gas accumulation; 2) "Red Sea" type thermal oozes with increased concentrations of noble metals; 3) ferromanganese nodules; 4) concentrations of metallic sulphides ("Black Smokers"); and 5) cobalt-bearing ferromanganese crusts on the summits and slopes of seamounts. Since then, the so called "White Smokers", containing sulphides of copper and zinc, have been discovered. The ore horizons (manganese, copper, nickel and other metals) of the sedimentary cover of deep-sea basins comprise a sixth type of mineral resource in the oceans. These horizons have not only a theoretical, but also a principal economic significance

Jan 1, 1995

1880 - 1930 - The Golden Years of Mineral Processing Technology

Sep 13, 2010

The application of methods using large diameter down holes has become an important facet in both the development and stoping operations of mines within the Aberfoyle group. Holes of up to 98 metres (vertical) and 78 metres (inclined) have been successfully used in stoping operations. A number of rises have been developed to meet ventilation, servicing and escape-way requirements. The most ambitious rise to date has been a..vertical 93 metre long by 4.50 metre square ventilation rise. Although some early problems were experienced, the ultimate successful completion of this rise has enabled the technique to be incorporated with confidence in future mining plans. This paper summarises experience in long hole rising techniques, their evolution from the original cratering concepts, and the approach to further development of these techniques.

Jan 1, 1982

By Liu C. H, Juang Y. F

Coal/gas outbursts were one of the rather difficult safety problems faced in the coal mines of this Country, with coal fields characterized by frequent disturbances of folds, faults and pinch-offs. With average mining depth about 500m below surface, several such accidents occurred with up to 500 tonnes of coal outburst. In recent years, after a series of improving countermeasures had been undertaken, gas outburst accidents had been greatly decreased. The characteristics of gas outbursts in Taiwan coal mines include relating to coal petrography, mining depth and the other deformation forces. All these have been investigated, trying to determine the parameter of outbursts under natural conditions. The preventive countermeasures include predicting tests, de-stressing boring in coal seams, the emergency procedures during outbursts and certain improving options.

Jan 1, 1988

By Mayer TE

The Granites Goldfield is located 550 km northwest of Alice Springs. Mineralisation was discovered in 1900 and intermittently worked along nine km of strike until the early 1950's, yielding a recorded production of 470 kg of gold. The geological environ- ment, pre-existing exploration drilling results, and an optimistic view on gold, prompted acquisition of the property by North Flinders Mines Limited in 1975. An agreement was signed with the Central Land Council in August 1983 and drilling commenced in the same month. In the past, gold was won from alluvial deposits, rich quartz veins and lower grade, disseminated stratabound mineralisation. The last is contained within a distinctive unit in the Mt. Charles Beds, of the Early Proterozoic Tanami Complex. This informally named "Host Unit" is a metamorphosed, chemical- pelitic sediment. The schist contains variable proportions of amphibole, quartz, garnet, clinopyroxene, carbonate and sulphide, inter- calated with recrystallised chert beds. Free gold occurs in several mineralised horizons within the Host Unit, generally conformably distributed within lithologic bands or at lithologic contacts. The Host Unit occurs within a sequence of metamorphosed pelitic sediments and intermediate volcanics. Although mostly confined to the Host Unit, stratabound gold mineralisation also exists in both Footwall and Hanging Wall Schists, usually within zones displaying certain Host Unit characteristics. The deposits may be loosely categorised as being of banded iron formation (bif) type, although some important differences are noted between them and classical bif type orebodies.

Jan 1, 1984

The coal basins that formed near the margin of Permian Australia were comparable in size with the Appalachian coalfields and with the European fields between Wales and Poland. They formed on the foreland side of a growing orogen in a system of linked transform basins formed by transtension on strike-slip faults. They were terminated and compressed when the Gympie volcanic arc was accreted to the orogen. Another huge system of Permian coal basins extending far inland from the Permian coast was also terminated when the Gympie Terrane was Accreted.

Jan 1, 1987

Conveyor belt haulage offers the advan tages of continuity of operation, minimum labour requirements, and the ability to handle large volumes of material over extended periods. However, breakdown of critical con- veyors in the system can cause undue and substantial losses in production output at the working faces, unless adequate surge bin capacity is incorporated in the haulage system. A conveyor belt simulation programme, code name 'Beltsim' was developed by Bucklen et al (1968) at the Virginia Polytechnic Institute in the U.S.A. and provides a quantitative measure of the performance of a conveyor belt network design. A limitation still exists with the computer programme and involves the inability of the programme to predict the necessary surge bin capacity to overcome conveyor belt downtime. The computer programme was modified to overcome this limitation, to simulate a con- veyor belt breakdown, and to provide a quantitative prediction of the surge bin capacity necessary to permit a modern mining system to operate effectively and continuously.

Jan 1, 1977

By Yamada K, Abe H

Magnetic scanning type mass spectrometers have been given improved sensitivity with a large dynamic range and considerable resolution by the addition of a computer-controlled electric equipment. A mass spectrometer equipped with this newly developed electric system was applied to studies of the activities of liquid iron-silicon alloys and of liquid iron-phosphorus alloys at 1600¦C. The range of silicon concentration was 5.8at%-51.1 Si= at%, and values of ySi -3.1+0.15 and es 11.5 +1.5 were obtained. The concentration range of phosphorus was 1.3at%-5.7at% and a value of eP=7.3+0.1 was obtained.

Jan 1, 1980

Coal Mining Land Use on the southern coalfields often preceded other land uses. Over the past century overlying land use has altered significantly, particularly with water supply storage development, road system building, railways, pipelines, electricity reticulation schemes and general urban develop- ment. National Parks were declared over coal bearing lands. Little regard was paid to the coal under the land surface by land developers, Government instrumentalities, central planners and the Metropolitan Water, Sewerage and Drainage Board and others, and little value was placed on this valuable energy source. These bodies derived no benefit from the under- lying mineral. In these circumstances, mine operators and such surface land users were put into adversary roles. Mass sterilisation of coal resources resulted. The loss of reserves continues, although the problem has become better under- stood. An Energy Impact Statement (EIS) submission by all surface land developers has been proposed as a means to justify the impact of the development on the coal reserves Beneath.

Jan 1, 1979

By Large RR

Precious metals in the Rosebery north-end orebody occur predominantly in sphalerite- galena-pyrite ore and to a lesser extent in massive barite mineralisation. Gold may also occur in the upper parts of pyrite-chalcopyrite ore (although this ore type is usually gold poor), in pyritic mineralisation lateral to base metal sulphide lenses and in the footwall (very patchy). Although present, remobilised precious metals do not occur in economically significant quantities. Mineralogically, silver occurs dominantly in tetrahedrite and, to a lesser extent, argen- tiferous galena. Gold occurs as electrum associated dominantly with pyrite and, to a lesser extent, tetrahedrite. Geochemical modelling suggests that silver was probably transported as a chlorocomplex, while gold was transported dominantly as a thiocomplex, although at high temperature gold was transported as a chlorocomplex.

Jan 1, 1987

By Stewart A. M, Price D

This paper presents recent findings concerning longwall caving mechanisms relating to Australian mining conditions and their effect upon longwall support requirements and behaviour. The findings are based on a program of intensive hydraulic support monitoring in a variety of Australian mining conditions coupled with geotechnical observations.

Jan 1, 1992

There are serious problems in forecast- ing accurately and achieving this goal depends on good quality information, correct assumpt- ions and sound analysis. planner. The forecaster must focus attention on a number of key areas of interest. These areas include major economic trends and changing GNP structure, consumption time series, end-use consumption patterns and substitution potential, accurately updating data bases (up to 5 years ahead), random factor estimation and examination of both long term and secondary mine potential. While metal price forecasting has suffered due to recent uncertainties, with increased importance on planning tools and cost analyses, it is still a necessary function. Forecasting is subject to the real world and the metal industry is made up of imperfect markets in a dynamic state. The real world provides the challenge to improve the accuracy of forecasting.

Jan 1, 1983

By Gupta A, Fung C. C

The hydrocyclone parameter d5Oc is estimated by the application of Artificial Neural Network (ANN). Results indicate that ANN performs equally well as compared to statically derived analytical formulae. Results also show that ANN will also be convenient in the on-line control of hydrocyclones.

Jan 1, 1996