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By King CJ

The C.S.A. concentrator of Cobar Mines Proprietary Limited was expanded in 1974 to treat 80 000 tonnes of copper-lead-zinc ore per four week period. Jaw crusher product is fed to two par- allel primary autogenous mills followed by a secondary ball mill. Each mill operates in closed circuit with cyclones. Improved control of grinding rate and product sizing has been obtained from this circuit compared with the system of two parallel single stage autogenous mills. The main operational variables are des- Cribed.

Jan 1, 1978

Heavy media separation serves to upgrade mill feed and reduce unit operating costs, allowing ores to be mined which could other wise be uneconomic. At the Aberfoyle mine at Rossarden in north-east Tasmania, a simple heavy media operation using a converted Akins screw classifier as a separating vessel, removes barren quartz from mineralised material. At the Cleveland mine at Luina on the west coast of Tasmania a more complex ore mix requires a versatile operation combining hydro-dynamic and static separation equipment to provide an efficient beneficiation circuit. The two operations are briefly described with a background of basic heavy media separ- ation practice.

Jan 1, 1978

By Price B. D, Staunton W. P

The Mineral Science Laboratory of the Government Chemical Laboratories has recently investigated various procedures for the analysis of the platinum group metals (PGMs). This investigation covered a number of methods for the extraction and preconcentration'of the PGMs from a wide range of geological materials. The nickel sulphide extraction technique proved to be overall the most applicable procedure. Flame atomic absorption spectroscopy (FAAS), electrothermal atomisation atomic absorption spectroscopy (ETA-AAS), inductively coupled plasma atomic emission spectroscopy (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) were examined for their suitability in analysing platinum group metals in solution. ETA-AAS and ICP-MS proved to be the instruments of choice due to their low detection limits.

Jan 1, 1987

When preparing an appraisal, valuation or feasibility study for a new mining project it is difficult to imagine the technical, economic, social and environmental context that the project will occupy in ten or 15 years time. This paper is about our ability to foresee the future, the choices available now in matching the project to that future context, and about the flexibility that exists in adapting the project to a changing environment. The author draws upon his experience of project reviews, valuations and feasibility studies in the mid to late 1980s in Australia and New Zealand to explore how the project context has changed since key decisions were made and what this tells us about decisions made today for future projects.

Jan 1, 2004

By Fuerstenau MC

Zinc cementation and carbon adsorption are both presently used for precious metals recovery from cyanide leach solutions. Each of these techniques exhibits unique processing features which renders them suitable to treat solutions with different properties and in different applications. In this study, the two processes are reviewed and compared. Operating data from a number of Merrill-Crowe precipitation and carbon adsorption plants in North America have been obtained and used in this analysis. The relative capital and operating costs for the two processes have also been considered.

Jan 1, 1993

The causes and impact of stability problems associated with longhole open stoping (LHOS) at The Zinc Corporation, Limited (ZC) and New Broken Hill Consolidated Limited (NBHC) are discussed and LHOS stability objectives presented. The development of appropriate rock mechanics techniques is discussed and the reasons for using contract research are explained. Reference is made to the rock mechanics techniques developed and in use. The requirements to effectively use these techniques are discussed. Features of the staffing policy which has been adopted to develop and apply the LHOS stability assessment and control techniques are Outlined.

Jan 1, 1983

By Rashkovski GB

Until recently amalgamation has been the main process forextracting large gold particles from gravity concentrates obtainedduring the dressing of ores and placer gold deposits.Development of new technology for treating the gravityconcentrates was necessary because of the harmful effect ofmercury on subsequent production processes and theenvironment. The harmful effect of mercury is particularlyevident in the resin-in-pulp process that is widely applied inRussia.

Jan 1, 1993

Consideration of the questions: (i) is it feasible to study groups of processes in a generalised way? (ii) to what extent does purpose affect the form of a process model? (iii) are there any significant, novel investig- ations which can be made by computer simulation? (iv) what long-term developments are desirable in extractive metallurgy? has led to some new broad objectives for research in hydrometallurgical process engineering. Propositions for grouping processes, developing models for different specific purposes, using a systems engineering approach and developing high technology processes are discussed, and the role of computer simulation indicated by reference to particular projects.

Jan 1, 1984

Deformation of the lithosphere by tectonic forces is investigated from both observational and theoretical standpoints. Global and regional geophysical data bases, coupled with the means for their rapid display and analysis, facilitate recognition of areas of the con- tinents and oceans where the response of the lithosphere to these deforming processes might fruitfully be studied. Gravity anomalies, from Seasat altimeter data and from land and shipboard measurements, provide critical infor- mation on the isostatic state of deformed lithosphere and therefore on its thermal and mechanical properties.

Jan 1, 1987

An Ore Reserves and Exploration System has been under continuous development at Mount Isa Mines Limited since 1970. The task of re-engineering the system has now begun, and the first stage is operational. This paper describes how the application of data base concepts, and table driving techniques has resulted in a design in which the input documents, validation procedures and file data content are redefinable by parameters, thus allowing the system to be tailored to suit varying geological Environments.

Jan 1, 1977

By Canterford JH

Current and future methods of data acquisition in hydrometallurgy are reviewed. Hydrometallurgical operations involve a wide range of chemical and physical processes for the recovery of metals and other products from ores and concentrates. Control of such operations requires information on the different liquid/solid and liquid/liquid mixtures being processed. Continuous. data acqui-sition for the liquid phases uses procedures already commercially exploited in other types of chemical plant. The major problem is the lack of robustness of measuring probes. Continuous analysis of the solid phases is much more difficult to-achieve because of the sampling and analytical techniques involved.

Jan 1, 1985

Acid rock drainage (ARD) derived from sulphide oxidation and the associated metal leaching is the most significant environmental issue facing the mining industry today. Under given hydrological and biogeochemical conditions, the local geology and mineralogy largely control the formation of ARD. The involvement of a geologist is therefore essential in minesite ARD assessment and prevention. The relevant tasks that a mine geologist may undertake at three major phases of a mining project are briefly described. Additional knowledge that a mine geologist should acquire in order to achieve proficiency in ARD assessment is also suggested.

Jan 1, 1993

A magnetometer survey 'was the Darkes Forest area between 1968. The instrument used was model MZ4 with sensitivity 9.4 conducted over part of 30th April and 3rd May, an ABEM torsion magnetometer gammas per scale division. The survey consisted of a closed magnetometer loop along lines cut for a previous magnetometer and seismic reflection survey by Wongela Geophysical in March, 1968. The magnetic results of the previous survey were not satisfactory in some areas and are presented as a comparison in instrumentation. Station separation in the present survey was 100 feet with tie-in readings at shot points of the previous survey (usually 1320 feet apart)

Jan 1, 1969

By Ribicic M, Kocar F

Surface lakes or water accumulation present a possible threat for the flooding of the underground mining works. Therefore, the criteria that define the conditions under which no flooding of the mining works can occur are of vital interest to the miners. The authors present the criteria that they developed for the Velenje lignite mine, Yugoslavia, and that take into account the elastoplastic behaviour of the rocks and the natural stresses involved in the deformable strata between the bottom of the lakes and the mine works as well as the extent of the direct caving-in process resulting from longwall mining activity. Fi- nally a generalization of these criteria to the other rock and stress conditions is discussed.

Jan 1, 1988

Gold recovery by catalytic copper ammonium thiosulphate solution has been studied. Such a process strategy is very attractive for leaching certain difficult-to-treat ores and presents lessened lixiviant toxicity compared to cyanide. Newmont Gold Company has evaluated the ammonium thiosulphate heap leach process for gold recovery from low-grade carbonaceous sulphidic refractory ores following biooxidation. The ammonium thiosulphate leach process has been studied in laboratory, pilot plant and demonstration scale. Satisfactory test results support the continuation of process development. However, the thiosulphate leach chemistry was found to be very complex. Maximum control of the stability of the leaching system is a key factor for success, especially for the heap leach process. Important solution chemistry is discussed in this paper.

Jan 1, 1997

The impact of computers on the mining industry has increased for the past twenty years in most parts of the world. The application of computers in the mining industry has been demonstrated in areas such as geological data analysis, ore reserve estimation, mine planning, and manpower training. There is also a general concern in this country regarding the computing background of graduating mining engineers from the Australian higher institutions of learning. This paper describes specific steps which have been taken at the Department of Civil and Mining Engineering, The University of Wollongong to provide adequate computing background to mining engineering graduates. Specific topics discussed include hardware and software available to students and how "computers" have been integrated into the mining engineering course.

Jan 1, 1986

By C Glassock, P Bodon, M Elias

Computer simulation is a well-accepted tool for modelling the behaviour of large or complex operating systems. Less common is the use of simulation as a design aid, but FluorÆs simulation group regularly applies discrete and continuous simulation models to assist with optimisation and risk management in a wide variety of mining, mineral processing and logistics applications. To demonstrate the wide applicability of simulation modelling as a design aid, this paper describes three case examples from FluorÆs recent work that cover both discrete and continuous operations.

Jan 1, 2003

By Xin J

In China, the State-run mines are currently practising an information card management system, to collect data about mine production and safety condition. Since large volumes of data will be obtained every day, efficiently and effectively processing data and sorting out valuable information will take enormous resources of manpower, if by hand. Therefore, an intelligent database system with easy data inputting was developed to assist information processors in data classifying, filing and retrieving. For analyzing and improving production performances, reliability models and production functions were embodied. The system was implemented on AST-286 in DBASE M. Preliminary applications have proved effective and successful.

Jan 1, 1991

Good morning ladies and gentlemen. It gives me great pleasure to talk to you today about a pet subject of mine, on when to mill and when to leach gold ores. According to Gold Fields Mineral Services of London, gold production in the United States in 1989 amounted to about 8.5 million ounces (259t), an increase of 29 per cent over 1988 and 67 per cent over 1987. The U. S. Bureau of Mines reports that from the major producing states of Nevada, California, Montana, and Alaska, some3.2million ounces of the 1989 production were produced from milling gold ores and 2.3 million ounces from heap or dump leaching. Ap- proximately 45 million tons of ore were milled and 140 million tons of ore were heap or dump leached.

Jan 1, 1991

Legislation for control of ventilation in New South Wales coal mines is contained in the Coal Mines Regulation Act, 1912, as amended. The standards set down in that Act were based on the needs of the industry at the turn of the century. Changes and additions to the original standards have been made to cater for mechaniz- ation of the industry and the introduction of modern developments such as the use of diesel equipment. Technological progress has been recognized by the requirement for monitoring of machines and return airways. The passing of the Coal Mines Regulation Act 1982 has ensured that there will be a revision and modernization of the regulations affecting day to day operations of the industry.

Jan 1, 1983