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By J Szymanski, S Planeta

In pursuit of optimising the cemented rockfill system fragmentation of the aggregate, while travelling through the surface-to-underground aggregate transport raise, was investigated and a æfines estimationÆ equation was determined. When used with the rockfill strength estimation equation, the fines estimation equation enables an accurate estimation of the compressive strength to be derived theoretically. Optimum fill raise orientation was examined and recommendations are given depending on the varying stope dimensions. If the maximum dimension of the stope is less than 30.5 m (100 ft), a single, centrally located fill raise will suffice. However, as the stope dimensions increase, the number and orientation of the fill raises becomes more complicated and each stope must be examined on an individual basis.

Jan 1, 1998

Saxonvale mine is a multi bench open pit coal mine developed to its Stage I capacity of 1.75 Mt/y of run of mine coal. Detailed engineering studies for the mine commenced in April 1980, approval to proceed with the development was received in July 1980 and first coal shipments were made in April 1982. The engineering and project management of the mine development was carried out by BHP Engineering. This paper outlines the design and site administration for the development and describes both the organisation structure and the control and administration procedures used by BHP Engineering to ensure that the project was Successful.

Jan 1, 1983

o Resource production is essential for society. o Demand for resources will increase as population grows.o Resource industries are the main consumer of trained geologists.o The lead time from(1) training to productivity(2) research to resource production is measured in years.o An adequate supply of well trained geologists and successful geological research is an important agent in ensuring cost effective, adequate supply of mineral resources for society. Therefore the main beneficiary of geological education is society itself.o Society is paradoxically apathetic or antagonistic to the resource industry because (1) it represents change(2) lobby groups working for other causes have successfully moulded a bogey man image for the resource industry in the public eye.Professional training and research for resource industries consequently lack popular support. Funding is at an absurdly low level in comparison with the economic importance of resource supply.

Jan 1, 1990

Towards Improved Hydrocyclone Models - Contributions from Computational Fluid Dynamics

Sep 13, 2010

Computer modelling is being used to simulate rock fracture, caving and stress redistribution about longwall panels with increasing confidence. The models are being assessed against field monitoring and have significantly increased the understanding of caving mechanics within the overburden. This paper discusses the modelling approach and provides some examples of its application to overburden damage and induced hydraulic conductivity. Computer models used in this study simulate the fracture process in the geological units throughout the overburden. Analysis of the mining induced fracture patterns and in situ joint patterns allows an estimation of the hydraulic conductivity within the overburden. The cubic flow relationship has been used in the examples presented.

Jan 1, 2005

By Canterford JH, Ritcey GM

With the development of new technology and materials of construction, chloride-based hydrometallurgical routes have gained accept- ance as a viable alternative to sulphate-based routes. A number of commercial and pilot plants built and operated over the last decade have provided invaluable experience and con- fidence in their use. Chloride hydrometal- lurgy, with or without pyrometallurgical pre- treatment, is particularly attractive for pro- cessing complex Cu/Pb/Zn/Ag concentrates, nickel mattes and chalcopyrite concentrates. This review outlines recent developments, dis- cusses advantages, as well as indicating some of the problems still to be solved.

Jan 1, 1984

This paper provides a financial perspective to the valuation of Australian resource companies and projects. Valuation exercises need, however, to be seen in the broader context of a thorough business appraisal, one that incorporates all disciplines employed in the resources industry. Fine tuning a discount rate or determining a particular capital structure is likely to be less important to valuation than an adequate understanding of industry dynamics and a company's likely performance in future years.

Jan 1, 1989

By Kellett KR

Gold Mining at the Lancefield Mine was commenced initially in 1897 and continued intermittently through to 1956 when rising costs and mine cave-in forced closure. The mine was redeveloped in 1981 and a new-oxide treatment plant commissioned, followed by a new refractory treatment plant in late 1982. Both these treatment plants are located within the Windarra Nickel Project plant area.The refractory ore is processed by fluidised bed roasting of flotation concentrates. This is carried out in two series connected reactors to maximise arsenic and sulphur eliminations and to minimise reagent consumption. For gold recovery the zinc precipitation process was initially used, to be later replaced by carbon-in-pulp.

Jan 1, 1984

By M L. Habner, S D. Munro

In a gold CIP/CIL circuit, adding new circuit water to a final tails thickener and then directing the thickener overflow to the head of the circuit significantly reduces the cyanide concentration at the TSF discharge spigot. The new water is used to dilute the final tails. The dilution and recycle of the tails in this manner may have the added benefit of reducing reagent consumption, in some cases to the point where the reagent savings justify the expenditure and Cyanide Code compliance is achieved at no extra cost. Potential circuit configurations and water recycles can be modelled by splicing a flowsheeting and thermodynamics package, such that changes to the composition of the water can be reduced to chemical speciation with a Gibbs free energy minimisation enabling a complete understanding of the circuit water chemistry.

Jan 1, 2007

A method is proposed for the determination of antimony in ores. Antimony is volatilized as antimony iodide by heating with ammonium iodide at a controlled temperature.The fusion mixture is extracted with hydrochloric acid and the antimony content is measured by atomic absorption spectrophotometry using an air/ acetylene flame. The time taken for analysis when comparedwith existing fusion and separation procedures is considerably reduced. Cations and anions likely to be present in antimony ores were also studied for possible interference effects but were not found to interfere.

Jan 1, 1972

By Downs M

The use of a cutting machine designed to allow simultaneous cutting and setting of roof supports has numerous advantages few development roads in coalmines. The use of such a machine with the added ability to cut a curved roof profile is of considerable interest for longwall development in thick coal.

Jan 1, 1998

The purpose of this paper is to outline the current status of financing in the Australian Gold Mining industry and to discuss a number of developments that have occurred during 1983/84.Recognising the importance of equity financing various equity issues, including project valuation, will be discussed against the backdrop of an industry experiencing both rapid growth and a changing structure.Nothwithstanding the current tax exempt status of the industry there is a trend towards more debt financing. A number of financing issues will be covered and it will be shown howvalue can be created through astute financing planning.

Jan 1, 1984

By Gibbons S. L, Ritchie I. M, Murr D. M

Fundamental studies on the transformations of iron oxides have been carried out and related to the solution conditions in the Becher process. The results show that a number of iron oxide interconversion reactions occur in the aeration reactor with the products depending on the pH, temperature and oxidation potential of the aeration liquor. It is concluded that the lack of process control in the aeration reactor of the Becher process significantly hinders the ability to predict and produce high quality single phase iron oxides of a consistent colour.

Jan 1, 1990

Chlorination of organic matter by direct injection of chlorine gas or hypochlorite has been investigated metallurgically worldwide with little understanding of the basic chemistry of the passivation mechanisms in- volved. In this paper, chlorination of carbon is attributed to oxidation-reduc- tions, resulting in surface halogenation of graphitic or amorphous carbon. It is proposed that chlorine and carbon interact to form thin coatings of chioro-carbon complexes that block the adsorption of gold cyanide com- plexes, thus passivating the gold adsorption sites of carbonaceous matter. Analytical, spectrographic, microscopic and electron-optical methods have been applied to demonstrate the proposed mechanism of chlorine-carbon bonding, as well as to evaluate the advantages and limitations of chlorination in the pretreatment of refractory carbonaceous gold ores.

Jan 1, 1991

By Dunne RC

The physical properties of an orebody require determination for virtually all mining projects, new and existing. The extent and regularity of such determinations being subject to the size and homogeneity of the orebody. Such properties have an impact at the design stage of new plants, with respect to equipment specification, and thus effects capital costs; and also impacts on the operating costs of new and existing plants, with respect to power consumption, production levels and part replacements. All of these can severely alter the bottom line and can be the determining factor in the economic viability of many projects.This paper examines some of the most common properties that are measured, the procedures utilised in determining these properties, and their variability under conditions of reproducibility, and to a lesser extent repeatability.

Jan 1, 1997

This paper explores options worthy of consideration in the management of S02 produced from the gold roasting operations at Kalgoorlie. Some of the options have relevance to other sources of SO2 in the region, eminating from nickel smelting operations. The paper considers the following options: 1. Capture of SO2 within the roaster where sulphur-containing reaction products are mixed with the calcine. 2. Processes in which the sulphur-containing products are bled separately from the stack for further treatment or for dumping as a waste. These include: Seawater-based scrubbing of SO2; Sulphuric acid manufacture as a feedstock for fertiliser production or for leaching of bauxite; its use as Caro's acid: and the production of value-added sulphur-containing reagents eg liquid S02 and sulphonic acid.

Jan 1, 1992

The Professional Standards Act responds to the growing problem of professional liability by introducing a mechanism whereby professional associations can have schemes approved. Those schemes include a cap on liability; a requirement for compulsory insurance; the development of risk management strategies; and the establishment of a complaints and disciplinary system. The Act is also designed to support and develop the concept of self-regulation by the members of occupational associations who provide services to the community by providing them with those tools. It implicitly accepts that self-regulation is preferable to statutory regulation and that self-regulation serves the interest of the community and of the providers of services. The Act arose from a review of professional liability commenced in 1988. The Attorney General's Department produced an Issues Paper, released in September 1989, which outlined in detail the extent of the problem. This was widely circulated and an extensive number of comment were received.

Jan 1, 1995

By M Eichorn

Running a successful reagent plant trial is not an easy task, especially when trying to achieve an incremental improvement in a highly variable process, such as flotation. Cytec aims to achieve one per cent recovery improvement with 90 per cent statistical confidence. Most concentrators experience large fluctuations in recovery and so the æmagicalÆ one per cent is difficult to detect. With the aid of statistical software, including REFDISTR (proprietary) and ECHIPR, Cytec have developed a unique approach to differentiate between daily operational variation and actual process improvement. This paper describes how Cytec runs a plant trial based on extensive laboratory investigation and detailed analysis of historical plant data using statistical techniques.

Jan 1, 2000

By Keast-Jones R

The relative merits of treating coal by flotation and spiral concentrators have been examined by tests on run-of-plant fines samples from three seams in the Wittingham coal measures of the Upper Hunter Valley. Flotation of the complete fines was found to be the most metallurgically efficient process with yields substantially superior to those obtained from treatment of only the deslimed fines. A strict comparison between spirals and flotation for the treatment of the deslimed fines was impossible due to differences in product quality. However, the results indicated that the performance of a flotation circuit would be equivalent, and sometimes superior, to that of a spiral circuit.

Jan 1, 1984

Construction of Western Mining Corporation's nickel refinery at Kwinana, Western Australia, commenced in July, 1968. Production of 15,000 tons per annum of refined nickel metal will commence early in 1970, The plant will also produce approx- imately 150,000 tons of ammonium sulphate0 The ammonia leach process which was developed by Sherritt Gordon Mines Ltd., and has been in operation at their plant at Fort Saskatchewan, Alberta, Canada, for the past 15 years, will be used at Kwinana. The refinery will cost approximately 435 million, and will employ upwards of 250 people.

Jan 1, 1969