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BlIP Minerals is a large, diversified, international mineral producer. This paper describes the company's operating strategy, and identifies the role of mineral processing in this strategy through three examples: the column flotation installation at Escondida in Chile, the leach-SX-electrowinning plant, proposed for Escondida, and the whole-ore roasting process being constructed for the Syama gold operation in Mali. It is concluded that the application of appropriate and sometimes novel mineral processing technologies can achieve significant benefits in reduced operating cost, improved product quality, and in some cases the exploitation of previously uneconomic deposits, thereby providing strategic advantages to the company.

Jan 1, 1993

Until the early 1960s the world aluminium industry was dominated by six principle pro- ducers with integrated activities from bauxite mining to aluminium production. The growth in consumption of aluminium since that time and the emergence of additional producers has broadened the market for bauxite. In addition the increase in the optimum size of alumina refin- eries has influenced competing metal producers to unite in large joint ventures to minimize alumina costs. From these bases the paper examines present and likely future markets for Australian bauxite; differing marketing phil- osophies for serving those markets; factors influencing successful marketing; and the sources and relative strength of competition which Australia faces.

Jan 1, 1974

The Australian underground contract mining industry has grown from almost nothing 25 years ago to the point today where half the countryÆs underground mines are using contractors to produce their ore and do their development. This growth was driven by the need to change poor industrial relations and work practices in sectors of the industry, along with the needs of many small gold mine owners to preserve their capital by using contractors to do their mining. The industry is dominated by two major privately owned contractors with a number of other publicly and privately owned contractors making up the balance of the market. This paper discusses the important trends in the contract mining industry and the directions it may take in the next few years.

Jan 1, 2005

There has been considerable attention in the literature to coarse sizing by wet and dry screening, but these methods have not proven to be applicable to the calculation of screen capacities for fine wet sizing, desliming and media recovery: A method is presented for the calculation of the size of screens for such duties, being based on the mean particle size of the oversize material on the screen which reflects the surface area from which the fines or media must be removed. Similarly for dewatering, it is the area from which the water must be drained. Desliming, media recovery and dewatering are each considered along with water require- ments both with the feed and as wash water.

Jan 1, 1984

By P McCarthy

Many mining operations developed in the last 15 years have not performed to expectations. Problems experienced include lower than planned development and production rates, geotechnical/stability problems, unplanned dilution, reduced metallurgical performance and unbudgeted capital/operating costs. Most of these problems can be directly attributed to decisions made on the basis of geoscience interpretations and estimates. Recent case studies continue to provide examples of unplanned events linked to the use of geoscience information. These studies illustrate the need to improve the way geological information is used in mine feasibility and operations. Comprehensive assessment of the consequences of inappropriate technical decision making is still rare; however, the information that is reported highlights the significant financial impact on a companyÆs bottom line.

Jan 1, 2006

This paper refers to the open cut mining practice developed at Western Mining Corporation's Kalgoorlie Gold Operations (K.G.O.). Mining activity was centred attwo areas, namely W.M.C.'s Siberia "Sand King" and"Missouri" open cuts plus W.M.C.'s "Great Boulder" and K.M.A.'s "Horshoe" and "Morrison -Hannan's Star" open cuts in Fimiston.Kalgoorlie Gold Operations was set up initially to look after W.M.C.'s open cut interests in and about the Kalgoorlie area. The first mine commenced was, the Sand King open cut, approx 75 km NW of Kalgoorlie. it was here that the requirement for a highly selective form of mining first became apparent.

Jan 1, 1984

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 B Sulistianto, D Carrugan a, R K. Wattimena

Geological structure at PT Karimun Granite Quarry, in Karimun Island û Indonesia, has three primary joint sets that cross between them. These primary joint sets are the principal factor influencing the geotechnical safety of this quarry. In order to get stable geometry of the quarry in terms of height, width, and slope for single and overall bench, we need an appropriate stability analysis method to prevent failure and maintain stability. The Universal Distinct Element Code (UDEC) is used for this rock mass system. The geometries resulting from this analysis have been implemented and have given a stable quarry until now.

Jan 1, 2003

In both exploration and mining, the laboratory is often seen as a cost rather than a profit centre. The aim in most mining companies is to increase profits by reducing costs, so the budget for the laboratory is under constant pressure.There is another option; to see the laboratory as the brain of the operation. By lifting the status of the laboratory and treating it as a profit centre, mine costs may be reduced in other ways, e.g. reduction in milling costs. This change of status will require investing more capital in better equipment, more training for employees and more employees to carry out project research.There are many examples of major costs being incurred because of inadequate laboratory work. Conversely, by spending more money on laboratories and their activities, overall costs can be reduced or profits enhanced.

Jan 1, 2002

Kensington is a joint venture between Echo Bay Mines and Coeur Alaska, a subsidiary of Coeur d'Alene Mines Corp. The venture is of equalparticipa- tion and is governed by a management committee with Echo Bay as the operator. The project site is 50 miles north of Juneau, Alaska on the eastern shore of the Lynn Canal. The mine and mill are being planned for a production rate of 4,000 stpd. Currently, probable reserves stand at just over 11.3 million tons grading 0.149 oz Au/ton. The project is now in final feasibility study with a production decision anticipated by the end of 1990. Commercial production would begin early in 1993. This presentation dis- cusses the anticipated mine, mill and support aspects of the project.

Jan 1, 1991

Petroleum exploration is proceed ing in Western Australia at an ever- increasing pace. Results in recent years have been very successful, with the discovery and development of the Barrow Island oilfield and the Dongara gasfield, and the discovery of several major gas-condensate fields on the Northwest Shelf. The Northwest Shelf discoveries will have a big impact on the economy of the State by providing an abundant indigenous source of energy. Prospects for further large dis- coveries are believed to be excellent. The most prospective areas are thought to be on the continental shelf in the Carnarvon, Browse, Perth, Canning, and Bonaparte Gulf Basins.

Jan 1, 1973

The nature of exploration in Australia is reviewed from its inception to the present time. It is seen as consisting of three phases: the first, prospecting; the second and third, mainly company-based activity. The first yielded the discoveries on which the mining industry was originally built. The great recent growth of the industry has been due mainly to the discoveries of the third. The technical, organisational, legis- lative and other aspects are reviewed. The overall result has been a very great increase in the known mineral resources and, viewed collectively, exploration is seen as providing the principal means of assessing, evaluating and building up the nation's mineral resources.

Jan 1, 1973

Regional problems, such as political risk and debt reschedulings, in Pacific Rim nations coupled with the price volatility of gold mean that multi-faceted financing packages are needed to offset the many risks inherent in a new gold mine development. The cross-border risks of getting money back out of a producing mine may require the involvement of export credit agencies, multilateral government banks, or political risk insurance. Variations on forward gold sales, gold loans, or offset structures can also enhance the flexibility and safety for the providers of both the debt and equity. The region will become as large a gold producer as South Africa by 1990. The large dollar amounts for both investment and revenues realised are of great significance to the economies of many of the Pacific Rim countries especially as a means to increase foreign exchange earnings.

Jan 1, 1987

Resource rent tax is a form of taxation or royalty, which only become effective at such a time as a pre-determined rate of return has been achieved by an operation. The offshore petroleum industry in Australia is already subject to RRT as is the Roxby Downs (Olympic Dam) Mine in South Australia. Both the mining and petroleum taxation regimes in Papua New Guinea include a resource rent tax component called Additional Profits Tax (APT). The implications of the current form of Additional Profits Tax for shareholder cash returns are that the tax burden on the operation may suddenly increase at some stage in the life of the mine, if and when the threshold level of profitability for the tax to be triggered is exceeded. From that point in time onwards the cash return to the shareholders on the capital invested is greatly diminished. For mining companies in Papua New Guinea, the effective tax rate increases from 35% to 57.75% as a result of the onset of Additional Profits Tax. This tax rate penalty is so severe that there appears to be merit in considering the concept of managing profitability through time rather than purely maximising annual pre-tax profits as is currently the case in most mining operations. This would have the benefit of deferring or perhaps preventing altogether the onset of the tax. One possible method for the effective management of profitability is through the control of average mining grade by cutoff grade manipulation. Traditional cutoff grade theory has usually considered taxation as a direct cost at a fixed or variable percentage of annual profits. As a result of this most analyses are conducted on a pre-tax basis. If tax is included in analyses it is usually present as a time independent function of gross profit. Additional Profits Tax is both time and rate of return dependent and therefore not adequately accommodated by currently accepted cutoff grade theory. A review has been made of the effects of resource rent taxes on both the investment decision-making process as well as possible development and mining strategies which may be employed by mining companies faced with Additional Profits Tax. The review includes examples based on the structure of Additional Profits Tax which is levied in Papua New Guinea.

Jan 1, 1997

The commercial outcomes from new mining projects or brownfields expansions often fall short of feasibility study forecasts because of technical under-performance. This paper: reviews past feasibility study performance; identifies the key drivers of underperformance; and proposes actions that can be taken to manage the risk of underperformance. There have been a number of published reviews of feasibility study performance since the 1970s. The results of these studies are summarised together with recent unpublished data. Key drivers of underperformance include inadequate metallurgical testing, simultaneously pushing a number of project parameters beyond comfortable limits and a failure to recognise the linkage between mining rate and head grade. Actions can be taken during the data acquisition phase and during the feasibility study to manage project technical risks. These generally require a more flexible approach to study management than can be achieved under a ælump sumÆ contract.

Jan 1, 2003

By James DG, Turner JH

This paper describes laboratory testwork for the beneficiation of a medium grade iron ore, using Wet High Intensity Magnetic Separation (WHIMS). Factors leading to the selection of machine type for this method of separation are discussed and the design of the WHIMS section flowsheet of an iron ore beneficiation production plant are described including methods to achieve operational flexibility and adequate protection of the WHIMS separating chamber. The results of the commissioning and operation of the production plant over several years are described, together with experience developed in plant operation. Data on recovery of hematite over the full range of size fractions treated is presented and compared with data in the literature. Potential methods of improving plant performance are discussed. KEYWORDS: Iron ore beneficiation, plant design, wet high intensity magnetic separation.

Jan 1, 1993

The Warner Process has been devised to produce zinc metal directly from sulphide, thereby reducing the requirements for purchase of large amounts of energy in a special form. The process conditions for a practical process have been evaluated in an extensive program of research and development at the University of Birmingham. Recorded data now exists to take the process forward to commercial use within the next five years. The industrial economics have been evaluated. The cost of making zinc metal from zinc sulphide ore can be substantially lowered due to the reduced energy cost, locating zinc production in the neighbourhood of the mines and increasing ore to metal recoveries - particularly for fine-grained and pyritic ore. Integration of a Warner Furnace with a zinc mine and concentrator can result in a highly attractive return on capital Invested.

Jan 1, 1993

EARLY HISTORYIt is 91 years since the epic discovery of gold at the eastern end of Kalgoorlie's main street appropriately named Hannan's Street after the prospector who found the first gold here on17 June, 1893.The Spirit that motivated the early prospectors in their search for gold in this thirsty sun-burned land, unmapped, uncompromising and difficult is characteristic of gold prospectors the world over. Conditions have changed since then substituting comparative comfort for previous austerity and privation, but the quest-ing spirit, the everlasting optimism, the perseverance in the face of frustration .and disappointment still exists.It exists with the prospector who more often than not is a company geologist; it exists with the shareholder enjoying through his investment a vicarious participation in this wonderful, exciting industry and not the least with those people who have chosen the goldmining industry as their career.

Jan 1, 1984

In the last few years it has become legal for women to work without restriction underground in some States in Australia. Since the mid 1970's there have been women graduates in mining engineering from several Australian tertiary institutions. Women from this group are the first females to have been employed to do manual work underground this century. The questions which arise are "What are the current parameters surrounding the employment of women underground?" and "What have been the experiences of those women who have worked underground?". In order to answer these questions, contact has been made with the various mining schools in Australia, the relevant government departments, the main underground mining companies, the relevant unions and professional associations, and other women who have worked undergrond. Personal experience as both a miner and a mining engineer at the CSA Mine near Cobar in New South Wales is also used.

Jan 1, 1988

By Tonkin D. A

Poor performance in the several stages of the magnetite recovery circuit, coupled with poor desliming through inefficient and over- loaded desliming screens, led to excessive magnetite consumption. An accurate and reliable sampling programme was established covering all outlets of the plant. Emphasis was placed on frequency of increments in an endeavour to detect extreme conditions of short duration. Systematic checking of the entry points to these outlets than identified those sections of the recovery circuit at fault, namely magnetite recovery separators and the heavy media cyclone product rinsing screens. More product rinsing water was provided, and modifications to the rinsing screens improved the efficiency of these units. Consistency of operation through automatic control of level eliminated the sudden massive losses in the magnetic separators. Load on the recovery circuit was then reduced by improvements to the raw coal desliming screens. A 50 per cent reduction in magnetite consumption was achieved.

Jan 1, 1974