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By Dance A

Highland Valley Copper recently implemented a system of measuring run-of-mine (ROM) ore properties and monitoring their effect on both mine and mill performance. These properties are principally ore hardness and size. For some years, Highland

Jan 1, 1998

The role of the mine geologist and the exploration geologist have diverged considerably in the last two decades. The principal focus of the mine geologist now is on ore resource management rather than ore resource discovery.

Jan 1, 1997

The paper presents the results of laboratory blasting and grinding experiments on a low-grade iron ore, investigating how blasting will influence the subsequent crushing and grinding operations. Increased blasting energy will lead to a reducti

Jan 1, 1998

The Queensland Phosphate Limited (QPL) Project is based upon the manufacture on world scale of High Analysis Fertilizers from resources located in north-west Queensland.High Analysis Fertilizers are produced from phosphate rock, sulphuric acid and ammonia.

Jan 1, 1993

By Jena P. K

Smaller deposits of high grade chalcopyrite or the concentrates of low grade and complex copper bearing ores, can be subjected to extraction processes other than smelting and converting. Low temperature chlorination and segregation processes are among those mentioned in the literature. In the present work, extraction of copper from a Brazilian chalcopyrite concentrate by slurry chlorination with chlorine gas at room temperature, dry chlorination by chlorine gas in the temperature range of 350 to 450¦C and segregation roasting of the calcined concentrate in the temperature range of 650 to 800¦C have been carried out. The effect of several experimental variables on the extraction of copper has been discussed in all these cases. Under optimum experimental conditions, 100 per cent Cu extraction was possible by either slurry or dry chlorination processes and around 86 per cent Cu by segregation roasting. For all the three cases, possible methods have been suggested to trial the studies on a pilot scale to assess their technoeconomic viability.

Jan 1, 1992

This paper will present a series of examples drawn for a number of Australian and international mining companies showing their recent attempts at optimisation of capital. The results will be compared, contrasted and discussed in the light of six factors that are considered crucial to any analysis of this subject. The factors are: ò the market availability of capital ò the corporate strategy and performance ò the capital structure appropriate to the corporate positioning within the industry ò the parties to the optimisation equation ò the measurement of success of optimisation The factors above are not mutually exclusive and are generally interdependent so their order above is of little consequence. Other papers presented at this conference will dwell in more depth on all these factors, therefore this paper shall focus only on the key elements of each factor. By way of summary this paper will also address the issue of the longevity of optimisation - is it temporary or long term.

Jan 1, 1991

This case study reviews the Charters Towers vein systems for potential open-pittable bulk tonnage resources in' stockworks, horsetails or multiple vein systems. The review summarises district evaluation undertaken over the last 18. months before specific drill evaluations.Historical mining from Charters Towers includes in excess of six million ounces at head grades of one ounce per ton. A review and structural studies show most veins as simple, tight systems without significant horsetails or multiple sheeted systems. In addition the normal gold content of the pyritic selvages ('formation') is low and disseminated gold is virtually absent. Shoots are structurally controlled on vein/vein and vein/contact intersections. Historically high production vein systems are hosted by .,.t o of the younger granodiorite phases.Geometrically most veins dip shallowly (from 45¦ to as low as 200) in a north or easterly quadrant. Flat dips permit open cut exposure of considerable vein area at a favourable stripping ratio.

Jan 1, 1986

By Huafu L, Ruishi N, Hongnian Y, Qinglong Z, Yangshen S

The Dongshan terrane was first recognized in 1984 (Guo,et al., 1984, 1989) as an old continental crust block of migmatized granitic gneiss in the Southeast Coastal Hercynian-Indosinian orogen, and it was thought to have occured on Dongshan Island, which has an area of less than 100 km? Recent research work has shed much light on the geology of the Dongshan terrane.The Dongshan terrane is approximately 40-50 km wide and 380 km long, trending NE. It runs from the region of the mouth of the Ming River through Putian and Huian Counties, Amoy and Dongshan island of Fujian Province to Nanao island of Guangdong Province, bordering the southern segment of the coastal region and coastal islands of Fujian and eastern tip of Guangdong Province. The Dongshan terrane is divided from the Zhejian-Fujian Mesozoic Volcanic Mountain Chains by the Changle-Shaoan fractural zone, and its eastern boundary is covered under water in the Taiwan Straits.

Jan 1, 1990

By Coronel PT

Like companies in other sectors of industry, mining companies are experiencing significant problems with low labour productivity, high labour turnover, and accidents. Increasingly, companies are recognising that good training is a vital factor in dealing with these problems. One such company is Aberfoyle Tin Limited. Early in 1979 the company engaged P.A. Consulting Services Pty. Ltd. (P.A.) to upgrade and formalize its miner training procedures. P.A. developed a programme using their Process Analysis Method of Training (P.A.M.T.) and trained a company trainer in its use. As a result of its application and the establishment of a formal training school, the rate of production of trained miners has been greatly increased. Despite some problems caused by lack of resources at the mine, the trainees graduating under the new scheme have been shown to be of comparable standard to those produced by the previously used "on the job" training method.

Jan 1, 1980

By A Nixon

The Australian mining industry has changed dramatically over the past 20 years in terms of mining methods, mining equipment and human resource policies. The industryÆs approach to safety and health in terms of attitudes, style of legislation, and risk management techniques has also changed significantly. These changes have had and continue to have major impacts on the design of underground mine ventilation systems. In some areas, trends are clearly emerging. In other areas, mine ventilation planning remains very æreactiveÆ and is performing poorly in terms of providing a safe and healthy work environment at a reasonable cost. New concepts involving the role of ramps and shafts, the provision of refrigerated air, æventilation on demandÆ and newe gress and entrapment approaches are likely to be incorporated into mine planning and operating practices over the next ten years. This paper discusses these and other trends and identifies some likely future developments in the area of hardrock mine ventilation.

Jan 1, 2005

Plenary Address Zinc is a trace element in all igneous rocks and its background geological occurrence roughly follows iron but at much lower concentration. Living matter reflects this abundance and zinc is an essential trace element for complex life forms. Thus, environmental issues include zinc deficiency in soils and/or water - and thus in local diets - and zinc toxicity evident in natural or modified ecosystems. Increased knowledge of the role of zinc in plant and animal metabolism emphasises the need to manage, within guidelines based on naturally occurring abundances, the concentrations of zinc in water, spils and in the food chain. Although recognition of the natural variability of zinc concentration provides some basis against which environmental protection standards might be set, the measure of environmental `pollution' is more commonly taken as the degree of change to natural, background levels, attributed to the particular land or water use activity. Environmental constraints on mining, processing and usages of zinc may have less to do with actual

Jan 1, 1993

Over the past decade most, if not all participants in the resources sector have been involved in initiatives to improve margins, reduce costs and improve business profitability. In many cases the initiatives undertaken have fallen short of their stated objectives, and in some cases have resulted in the terminal decline of the underlying business. In reviewing why many such initiatives fail, a common theme of arbitrary cost reduction and a focus on minimising cost as opposed to maximising value and cashflow emerges. This paper proposes a structured process that allows mine owners and managers to develop an understanding of their cost structure and optimise production and cost outcomes from the business. The broad objective of cost optimisation is to create value by getting more out of existing and new assets by focussing on operational areas, particularly production and maintenance. The paper uses practical examples to highlight the application of cost driver trees as a mine improvement tool.

Jan 1, 2002

Late Palaeozoic and Late Mesozoic phases of widespread overprinting have obliterated most of the primary magnetization signature of the Tasman Fold Belt. Palaeomagnetic programs of a regional extent offer best prospects for identification and interpretation of such secondary magnetizations and for isolation of any remaining primary magnetization. In 1983 the BMR initiated a regionally oriented palaeomagnetic study of the Tasman Fold Belt to obtain palaeomagnetic constraints on the tectogenesis of the fold belt. Particular attention is being paid to the analysis of possible differential movements between suspect or- tectonostratigraphic terranes within the Tasman Fold Belt and the respect to cratonic Australia. Work has concentrated so far on the Cowra Trough-Molong High region of the Lachlan Fold Belt and the New England region. Pilot sampling has been carried out in the Gympie region. In addition Palaeozoic sequences are being studied from the Amadeus Basin and the Ngalia Basin to refine the palaeomagnetic reference frame of cratonic Australia.

Jan 1, 1987

On the basis of the data known on formation, characteristics and stability of solute heavy non-ferrous metals under different temperature and pressure conditions and different concentrations of substances dissolved it is found to be possible to obtain a condition of mineral formation resulting in selective production of free-floating minerals. This process of forced mineral formation has been taken as a basis of new methods of refractory copper raw materials concentration, complex processing of lead dust from copper smelting plants, lead flotation tailings final concentration and of those of polymetallic ores concentration. This list of effective utilisation of the process is not exhaustive (Bekturganov Abishev and Shkodin, 1987; Bekturganov and Sim, 1987; Bekturganov, 1988; Abishev and Bekturganov, 1989; Bekturganov, 1989a). To understand the character of the sulphurising thermodynamic and kinetic examination have been done. Analysis of conditions of the newly formed mineral associations formation and stability facilitates the elaboration of methods of improvement of results of the valuable components selective separation.

Jan 1, 1993

By M D. Kuruppu

Fleet operational effectiveness is fundamental to any operation, becoming highly topical in mines experiencing less than optimal output from their fleets. It is an all encompassing aim to identify those factors that could be improved within production and suggesting solutions in order to optimise the existing fleet and obtain the highest return on capital expenditure. The fleet operational effectiveness of a large open pit truck and shovel operation in Western Australia was examined and a study was undertaken allowing identification of areas falling below target. The annualised hours and production downtimes were investigated to quantify the potential gains of improvements in these areas. The project aimed to maximise direct working hours through determination of the main issues hindering performance. External and internal factors were considered and a continuous improvement program (CIP) was developed. The CIP aimed at internal site-based improvement teams to identify and implement solutions for improvement on a day-to-day basis. Strategies were then identified for the implementation of the proposed changes.

Jan 1, 2003

Separation in magnetic fluids is one of the modern techniques that offer a unique approach to material manipulation in a broad spectrum of industries. Its wide-scale application has been restricted so far for a variety of reasons, including limited throughput, inefficient recovery of magnetic fluids and the cost of commercially available magnetic fluids. This situation has changed recently. Very selective separators, with automated density control, capable of treating a variety of materials in a wide spectrum of densities and particle sizes have been built by DebTech and applied in the diamond industry. Technology for the recovery of magnetic fluids has been developed and low-cost magnetic fluids, with high magnetisation and low viscosity are being produced on a production scale. Scale-up of the technology has been addressed and units capable of treating large tonnages of material have been designed. Such a development thus offers the minerals industry a technology that surpasses the existing technologies in selectivity, efficiency and versatility

Jan 1, 2000

By N J. Betts

This paper aims to build on the strong emphasis that was placed on safety in the Sydney AITES-ITA Congress in March 2002. It will do this by comparing safety records from some major tunnelling projects in Europe and Australia over a period commencing in the second half of the 19th century to the second half of the 20th century and examining reasons for the apparent marked improvement that appeared in the 1980s. Further by looking at the relationship between this improvement and current trends in the australian industry by means of a detailed review of the safety record for the Northside Storage Tunnel project in Sydney which was completed in mid-2000. The paper will conclude by providing a summary of the progressive approach adopted by the minerals industry in australia and summarising the current state of tunnelling and underground construction in australia with respect to recently completed projects and potential major initiatives.

Jan 1, 2003

During conventional eddy current separation, a repulsive force is applied to metallic particles by placing them in a rapidly changing magnetic field generated by a spinning magnetic rotor carrying an arrangement of alternate magnetic poles. This method works effectively for larger non-ferrous metallic objects, such as aluminium cans, but as the metallic particles become smaller, the bulk repulsive force on the particles is increasingly replaced by a rotational torque. Therefore, for small metallic particles it makes sense to use particle rotation, rather than particle repulsion, to effect a separation. Eddy current separators using particle rotation are similar in construction to present separators, but are designed to produce a rotating field of essentially constant angular velocity and field strength. Practical and economic particle rotation eddy current separations are possible down to particle sizes of about 200 ¦m, but separations, at probably uneconomic rates, can be carried out on particles as small as 50 ¦m.

Jan 1, 2000

By Kim YC

An alternative development drilling strategy to the one currently in use at an open pit mine was investigated using geostatistics for a portion of the pit. The massive orebody, the 3-D nature of the problem, and the location of ultimate pit limit in the study area all created some unique problems in devising the development drilling strategy. Rather than using confidence interval of the global reserve estimate as the main criterion for development drilling, the confidence interval of short and medium range mine planning blocks was used as the objective. Based on somewhat arbitrarily selected level of confidence, the results from the study showed that a total of 50 diamond drillholes (DDHs) rather than the planned 62 DDHs is sufficient in the study area, if the selected confidence levels are acceptable to the management. The paper also emphasizes the importance of particular objectives being used in development drilling and how they influence the "optimal" placement of the development drillholes.

Jan 1, 1986

By Kruse JW, Kjar AR

Recently there has been increased recognition o'f the cost savings that can be achieved by the greater use of offsite preassembly for the construction of industrial plants. Preassembly is a method of construction which involves considerable offsite assembly of complete sections of an industrial plant in established fabrication shops. The preassemblies are transported to the plant site, often by large and oversize transport systems where they are set on prepared foundations, finished and interconnected to other sections of the plant as required. The concept of preassembly is not new, but widespread interest has been shown because site construction costs in all parts of the world have increased rapidly and often at a greater rate than in established fabrication areas. Particular interest has be focused on remote, isolated and inhospitable plant site locations. These areas require the import of skilled labour, the payment of high labour rate premiums and the development of infrastructure to support the workforce for the duration of the construction period.

Jan 1, 1983