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We live in a world in crisis. One where the tides of change run ever faster. Where the only thing we can be sure of is change itself. The challenge we face, therefore, is not how to resist the forces that move us nor even to try to predict where they will lead us, but to harness their energy and use their momentum to find new and innovative solutions to problems that can seem intractable. Indeed, crisis is often the catalyst which energises a business to change its technology and to form a partnership with a company which specialises in pioneering new technology.

Jan 1, 1993

Poorly designed sampling protocols generally result in high project risk by artificially increasing grade variability (ie the nugget effect). Sample collection, preparation and assay protocols that suit the ore type, together with QA/QC systems, will reduce this risk. All reporting codes (eg JORC, 2004) require the Competent Person to consider the quality and implication of sampling and assaying programs. High sampling errors beget higher project uncertainty; despite this fact, sampling does not receive the attention it deserves. The case studies presented show that many sampling issues frequently go unrecognised or unaddressed, resulting in poor project decisions during exploration through to feasibility and production. The overall conclusion is that correct sampling is critical to mining project success and that there is often a need for its optimisation.

Jan 1, 2007

The kinetics of the hydrogen reduction of iron oxides in granular calcined bauxite were studied at 550-1,050°C in a shallow bed reactor. The iron oxides behaved as a dispersion of particulate iron oxide in a porous alumina matrix in which the iron oxide particles were reduced independently. The observed rates of reaction were found to be virtually independent of the bauxite grain size. At 800,°C and above, the reduction was multistage, Le.1. Fe203 +2Al203 (matrix) ?2FeAl204, and2. FeAl204? Fe0 +Al203.Reaction 1 was very rapid. Reaction 2 was much slower, the latter stages being controlled, at least in part, by phYSIcal changes of the Fe0 and a-Al203 produced in the reaction. Owing to the observed nature of the material, the reaction rate controlling steps could not be determined.

Jan 1, 1972

By Shiels O. J

The paper reviews developments in general galvanising in Australia, including a brief history of the industry and its technology. The changes in galvanising process technology are covered, as well as developments in galvanising bath design, materials handling and pre-treatment. Developments in zinc management through the use of aluminium and nickel alloys are discussed. The paper addresses the cost components of general galvanising and relates this to the competitive position of general galvanising against other coatings used for protecting steel. The environmental aspects of the general galvanising industry in Australia are outlined with respect to the utilisation of process chemicals, problems associated with their disposal and developments in filtering and regeneration of process solutions. The current status of the industry is assessed in terms of zinc usage and usage trends. Likely changes in technology which may impact on the general galvanising industry in the future are reviewed.

Jan 1, 1993

By Summers DA

Faculty at the University of Missouri-Rolla have carried out research on the application of high pressure water jets as a means of excavat- ing coal for over 15 years. During the course of this time, a number of different concepts have been explored--the most recent of which has been to use high pressure water jets as a means of extinguishing an underground coal seam fire. This paper will examine the use of some of these technologies and will consider the results as a basis for discussion of further applications of water jets in the future. The structural pro- perties of coal which distinguish it from other adjacent geotechnical material and provide a considerable advantage to water jet cutting, will also be presented and the advantages of using this tool will be discussed.

Jan 1, 1986

By Brown P. L

A study has been made of the geochemistry of the Ronneburg mine district as input to the overall management strategy for the rehabilitation of the mine site. The study drew on the geological data and information store developed over the 40 years of mineral exploration and mining at Ronneburg, and on chemical data from the literature which described the chemical processes of weathering, oxidation, dissolution and precipitation of minerals. The geochemical processes were divided into three groups based on their rate of reaction. Fast processes were assumed to proceed to equilibrium and were modelled using equilibrium chemistry equations; slow processes were assumed to be proceeding at a quasi-steady state rate and were modelled using chemical rate equations; very slow processes were assumed to have no role in describing the geochemistry for rehabilitation purposes.

Jan 1, 1995

By Concha F, Sampaio R

In most of the literature, the hydrocyclone is viewed as a black box in which only global variables are present and where the equations are obtained by curve fitting. Recently some work has appeared where the Navier Stokes equations are solved numerically in the hydrocyclone geometry. However, in all of these works the air core surface, which has an important influence on the hydrocyclone dynamical behaviour, is modelled as being a cylindrical surface of fixed radius. In this work, we model the surface of the air core as a free-boundary which has to satisfy a jump condition, the Young-Laplace equation, relating the physics to the geometry. Based on this model, we are able to explain, qualitatively, some phenomena that have puzzled research workers in the field for many years, and can show, through the air core behaviour, the influence of material parameters on the performance of the hydrocyclone.

Jan 1, 1993

By Burgess J

Present practice of lead-zinc flotation at North Broken Hill Limited is described and factors influencing plant objectives and performance discussed. Mineralogical examination of final flot- ation products showed mineral liberation to be 94T complete and size by size metal recovery tables indicated a need for finer grinding to improve lead and silver recovery, but coarser grinding to improve zinc recovery. A steady grinding circuit, at constant ball mill power and cyclone overflow pulp density, is found desirable for satisfactory flotation circuit operation because instabil- ity in the grinding circuit inevitably leads to flotation instability and as a consequence less than optimal flotation operation. Remov- al of the variable lead flotation middling product from the grinding circuit decreased grinding instability.

Jan 1, 1978

Maximising margins in today's competitive international commodity markets demands superior productivity. This requires more than selecting the best equipment. It requires continually improving the efficiency of production, commercial, marketing and administrative processes under the control of solid modern management systems.This paper introduces an integrated way of working that includes proven management systems for successfully changing work practices and attitudes, developing managers and increasing accountability. It introduces a proven methodology for systematically involving people in sustained true continuous improvement of processes for maximising productivity, safety and revenue while minimising costs.

Jan 1, 1998

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 Nyamekye GA, Subramanian S

Adsorption tests have been carried out to elucidate the interaction mechanism between dextrin and sulphide minerals. Sulphides such as galena and heazlewoodite exhibit high affinity adsorption over the pH range that coincides with the iep of lead and nickel hydroxides, and is suggestive of chemical interaction. The adsorption behaviour with respect to the sulphides of copper is of the low affinity type, and follows a different pattern. The adsorption studies on graphite, support the chemical interaction mechanism, with the metallic impurities serving as adsorption centres. In conformity with the proposed mechanism selective separation of galena from chalcopyrite and heazlewoodite from chalcocite has been Achieved.

Jan 1, 1993

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

The energy input requirement to produce the molten slag associated with iron production to the modern Australian blast furnace, is estimated to be 2.OMJ/kg. In converting blast furnace slag to products of higher commercial value, advantage should be taken of this energy content by transporting molten slag from the furnace for beneficiation and processing in the molten state at an "off furnace site". The refined slag melt may then be converted into a variety of products for use in the building and construction industries, e.g. slag cement, slag sand and slag aggregates, insulation wool and various slag ceramic products. Some results of studies into slag melt beneficiation and conversion processes involving both molten and cold granular slag raw material, are presented.

Jan 1, 1979

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 George CW

Western Mining Corporation (W.M.C.)operate a 30 000 tpa nickel refinery at Kwinana, W.A. using the Sherritt Gordon Process. Following ammonia/air leaching of sulphideminerals and subsequent copper removal, nickel metal is produced as powder by hydrogen red-uction of the ammonium sulphate-rich solution. Batchwise reduction in pressure autoclaves is preceded by an oxidation/hydrolysis step to ensure nickel powder quality.The reduction process is energy intensive, requiring high temperatures and pressures. Present energy requirement is 24 GJ per tonne of nickel reduced. Of this, 95% represents steam and hydrogen consumption and 5% electric power. The design and operation of the red-uction circuit is reviewed, outlining the main areas of steam and hydrogen usage.

Jan 1, 1985

By Meakins R. L, Talaska A, Kenny D, Haycraft J. A, Dickson B. L

A vehicle-mounted radiation detector interfaced to a microprocessor called PRAM (programmable radioactive analyser mobile) has been developed to provide grade control for selective mining of a soft rock uranium ore. The grade of ore over which the vehicle passes is determined and indicated by several coloured lights to a pegman who walks behind the vehicle. Coloured pegs are then laid out to mark the uranium grade ranges on the floor of the mine pit. Comparison between grade ranges determined by the PRAM and by prior drilling and downhole logging at the Yeelirrie deposit, Western Australia indicate good agreement. Use of the PRAM decreases the cost, manpower and time required to grade extensive areas of a mine pit floor.

Jan 1, 1982

Australia had been enjoying a market boom led by the mining sector and West Australian mines were leading the way to satisfy the massive demand for our natural resources, especially from China. However, the Apache gas explosion on Varanus Island, 97 km off the west coast, has clearly demonstrated how the unexpected can suddenly impact on profitability and investor confidence for the mining industry. Risk management with contingency planning can provide the most cost-effective solution to help ensure mining projects are successful. For this discussion we will focus primarily on contingency planning, CP for mining projects à and how to plan for the unexpected. The Apache gas explosion will be our example æUnexpected EventÆ. Insurance may provide financial compensation but it will not protect your reputation as a reliable supplier or prevent damage to investor confidence and future mine projects. However, contingency planning can provide real protection for mining projects à to survive the unexpected.

Jan 1, 2009

The history of the discovery. and successful development of the offshore Gippsland Basin oil and gas fields has been well docu- mented in contemporarary and more recent industry and profes- sional literature. The various articles, papers and books record fairly balanced views and comments as to the nature and results of the explora- tion effort, and factual data concerning the subsequent develop- ment of the fields and facilities concerned with petroleum production in the Bass Strait and Gippsland environment. Recommended reading for those interested in the scientific and technical aspects of the Gippsland Basin developments and the search for petroleum in the Bass and Alway Basins includes the available library contained in the publications of The Australasian Institute of Mining & Metallurgy The Commonwealth Mining Congres since 1960 The Australian Petroleum Exploration Association The Geological Society of Australia The American Association of Petroleum Geologists Various Commonwealth and Victorian Government instrumentalities Trade Journals

Jan 1, 1988

The Australian lead-zinc industry faces a future in which the world market is likely to show at best only minimal growth and in which there will be increasing competition. Its production facilities use mature technologies employing expensive labour and increasingly costly energy in a country which demands the highest standards of environmental performance. Returns on investment are already unsatisfactory.Technology for survival would appear to indicate a need not only for more efficient capital, labour and energy usage combined with improved environmental performance, but also flexibility to handle more complex materials than the traditional, virtually single metal concentrates. This offers the potential for improved overall economics from the mine onwards, but will demand efficient separation and by-product recovery processes.In the lead industry these problems are being addressed in several emerging technologies. With zinc, the situation is less clear.

Jan 1, 1985

By Rao SR, Finch JA

Sphalerite flotation without Cu activation in the presence of iron ions has been reported and studied as a function of pH, dissolved oxygen content and pulp potential with both single mineral and ore samples (Leroux, Rao and Finch, 1987; Xu et al, 1992; Zhang, Rao and Finch, 1992). The flotation was attributed to ferric hydroxy xanthate. As a prelude to surface analysis to try to identify the species responsible, bulk precipitates formed from iron salt and xanthate solutions under different conditions were obtained and analysed. Analysis techniques included ultraviolet spectroscopy,infrared spectroscopy, X-ray diffraction and Mossbauer spectroscopy. It is tentatively concluded that the bulk precipitates contain three ferric components, two hydroxy xanthates (Fe(OH)2X and Fe(OH)X2) and iron oxide (FeO.).

Jan 1, 1993