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For various reasons, the maintenance of shaft structures is becoming an increasingly important factor in the operation of underground mines. Deterioration mechanisms related to operation of the shaft are identified as corrosion, mechanical damage, fatigue damage and wear. Deterioration mechanisms related to rock movements are identified as vertical strain, ride vertical closure and squeezing. Analytical procedures for assessing this deterioration are discussed, and it is shown how acceptance criteria are developed and implemented. In order to track the deterioration of shaft structures, shaft inspections are undertaken, but the information is often not well documented. Formalised procedures for capturing and recording information, and then processing the information are presented. Finally, two case studies are briefly described to illustrate how these procedures have been implemented in practice, and what benefit has accrued to the mines concerned.

Jan 1, 2005

The production of copper by the Outokumpu direct blister process commenced in July 1988. The problems and incidents encountered in commissioning the main smelter equipment are outlined. Early difficulties were encountered in process control, hot metal handling, dust buildup in the off gas handling equipment, waste heat boiler tube failures, foam over of hot metal into the waste heat boiler and failure of ancilliary equipment.

Jan 1, 1989

By Reifenstein A

ACIRL's petrographers apply microscopic techniques to coal exploration, production, preparation and processing problems and research investigations as well as provide a commercial service for quality control of export coal shipments. This paper describes a number of case studies of applications of petrography to coal industry problems and coal research, including

Jan 1, 1989

The mined-out Old Waite volcanogenic Cu-Zn deposit lies in the Noranda mining district of northwestern Quebec. The deposit has a distinctive pipe-like zone of alteration beneath the massive ore, extending into the stratigraphic footwall. The hydrothermal metasomatism within the alteration pipe produced a concentric zonation. with a peripheral quartz - sericite - chlorite mineral assemblage surrounding an axial core of magnesian chlorite - Phlogopite.

Jan 1, 1989

By Crawford J

The paper asks the question 'Why Limit the HYDROTRANSPORT of material to the confines of your washplant'.A brief historical review of widely accepted slurry transport operation establishes that we are not talking about new technology - simply applying proven experience to an innovative continuous system.The paper reviews a simple potential application and compares capital and operating costs with conventional trucking.No attempt has been made to develop a complete mine plan and the comparison has been limited to material transport costs.

Jan 1, 1992

As the surrounding environment continues to change and evolve, mine managers face a changing climate of expectations. TodayÆs mine managers must juggle competing pressures to deliver sound social, environmental and economic results. Leadership is a fundamental tool for the effective mine manager. Whilst mine managers require solid technical and operational skills, importantly the manager must be able to engage a workforce, build and retain employees and seize opportunity for growth and development when presented. An important tool for engaging employees in the business at Rio Tinto Aluminium is the business improvement programme. At Rio Tinto AluminiumÆs Weipa mine, the business improvement methodology Six Sigma is used to deliver measurable, sustainable outcomes for the business. The next step in Rio Tinto AluminiumÆs improvement journey is to implement Lean Manufacturing at all managed operations. The operating environment for mine managers continuously evolves and effective mine managers must be flexible and adaptive to meet challenges. Governance and regulation constantly change in an environment of commodity cycles and finite resources. This increases pressure on the economic return achieved by the operation. As such, effective mine managers must be aware of and manage the operating environment û the broader, issues-based environment not just the immediate day-to-day responsibility of mine managing. This includes delivering on safety, community and environmental priorities. At Rio Tinto Aluminium, part of managing the business is via investment in the area of social partnerships to engage employees and the broader community in Rio Tinto AluminiumÆs commitment to sustainability. The Future Reef partnership entered with the Great Barrier Reef Research Foundation in 2005 forms an important part of Rio Tinto AluminiumÆs climate change strategy. This four-year, A$1 million investment funds programmes looking at the effect of ocean acidification on the Great Barrier Reef. The partnership is a unique example of industry and science working together on an area of mutual and national concern. Modern mine managers require a broad set of skills to effectively deliver outcomes. TodayÆs mine managers must make innovative and courageous responses to determine todayÆs strategy for tomorrowÆs future.

Jan 1, 2006

Instantaneous outbursts have occurred at Metropolitan Colliery from the pick and shovel work of early days to the modern mining techniques of today. Developments have been the introduction of an emission index to measure the proneness of the coal to outbursts, drainage and destressing by large diameter holes, attempts at higher productivity by the introduction of pulsed infusion shotfiring and improvements in ventilation. The future plans and aims for the Colliery include prediction of outbursts, seam gas pre- drainage and longwall mining.

Jan 1, 1980

A low grade, refractory ore gold mine with high striping ratio such as at Macraes is always challenged in ways to improve margins. Common practice approaches used at OceanaGold Ltd Macraes are to maximise grade delivery, optimise recovery and reduce unit costs, as well as take any opportunities to incorporate new technologies and implement enhanced commercial strategies.   The Business Improvement (BI) programme was implemented across the Macraes operations in late 2003 and is being rolled-out to all other parts of the business. The core focus of BI at OGL is to: +        increase revenue, +        reduce cost, and +        improve processes.   A dedicated BI team comprising of a manager, team leaders and business analysts were engaged to identify and manage a series of opportunities to reduce operating expenses, optimise capital outlays and generate extra revenue. The Business Improvement Programme, though in its formative phase, has begun a cultural change within the organisation. Many people are starting to challenge the way they do things and are looking for ways to continually improve business performance.   The BI team encompasses individuals from different departments who can offer the diverse skill set necessary to produce intended results. The current team is made up of a BI manager, BI Team Leaders in Mining and Processing and analysts from Mining, Processing, Commercial and Plant Maintenance workgroups. A team member has recently been formally trained as a Six Sigma Black Belt. ] The BIÆs team role is to assist in the establishment of project management processes for each improvement idea. In addition the team will assist in tracking implementation, identifying and unblocking restrictions and limitations as well as setting up metrics to quantify the level of benefit returned and sustained.   From a more strategic point of view, the BI team is advancing the Business Improvement capability of the company by developing long term Communication and Training strategies. These strategies will set the direction of BI initiatives in the years to come to: +        educate the OGL workforce in basic BI techniques, +        assist the OGL workforce in applying basic BI techniques, +        communication the direction of BI in OGL, and +        close the information feedback loop to facilitate transparent communication between the OGL workforce and the BI team.

Jan 1, 2004

By Dunstan N, Valentine C

Gas power was first used on the Sons of Gwalia mine in January 1911, when a twin-cylinder Crossley engine of 167 hp was installed to belt-drive a 112 kw 550-volt ac generator. This engine was connected with a No 8 Crossley up-draught suction gas producer, using mulga charcoal as fuel.A second Crossley engine, of 400 hp direct-coupled to a 550-volt ac generator, was installed in 1912, and operated by a down-draught wood producer.This was followed by a large Kynoch twin tandem four-cylinder engine, rated at 660 hp, sea level, with a rope drive to the crushing and treatment sections of the plant.These engines operated until January 1921, when the plant and power house were destroyed by fire. After the fire, both Kynoch and second Crossley engines were salvaged and reconditioned and they continued to give useful service for some years.

Jan 1, 1932

By Sorokin M. L, Komkov A. A

Flash smelting of nickel sulphide concentrate has been practiced at WMC's Kalgoorlie Nickel Smelter for 20 years. The mineralogy of the concentrate from the original mines was particularly suited to this process. However, taking a strategic view, potential new processing routes should be fully evaluated as possible replacements for the current technology. The Vanyukov process has been under development in Russia for the past 40 years and has been successfully applied on a large scale to the smelting of copper concentrates, at two locations - Norilsk and Balkhash. The potential for the application of the Vanyukov process to the smelting of nickel concentrates offers a number of processing advantages, including smaller reactor and decreased dependence on fuel oil. This paper reports on preliminary investigations into the application of the Vanyukov process to the smelting of nickel concentrates. At this stage the investigations are limited to semi-quantitative comparisons and modelling studies.

Jan 1, 1992

An increase in the silver to gold ratio with increase in depth in the main ore shoot of the Crown- Crescent lode in the Emperor gold mine, Fiji, was found to be due mainly to vertical zoning of gold-silver tellurides. The zoning resulted from

Jan 1, 1980

By Sparrow G. J

In a recently completed AMIRA project, 20 samples were searched for gold mineralisation using the automated location facility (ALF) for rare phases on a scanning electron microscope in the CSIRO Division of Mineral Products, Melbourne. The samples were submitted by mining companies in Australia, and Papua New Guinea, and included crushed ore samples, cyclone overflow and underflow products, a flotation concentrate, and 12 tailing samples. Their gold contents ranged from 600 to 0.2 g/t An. Native gold and gold minerals including a gold telluride, gold-silver tellurides, and a gold bismuth mineral, were located in the samples as free grains and associated with other minerals such as pyrite, magnetite, hematite, ankerite, copper sulphides, silicate minerals, and quartz. In the highest grade samples, both micron sized and 200 ¦m grains of gold were found with ALF. It would be difficult to locate such d wide size range of gold in a manual search. Gold mineralisation was located in the tailing samples assaying 0.4 g/t An and higher. In several tailing samples coarse grains of native gold over 40 p.m in size were located. One grain was estimated to have contributed 40 per cent of the gold in the sample. As well as locating gold mineralisation, the ALF examination resulted in the identification of uranium, mercury, and bismuth minerals in the samples. Knowledge of the distribution of these minerals in processing streams could be important in the operation of a concentrator.

Jan 1, 1992

By Jaczkowski B. M, Cox T. J, Domfeh I. A, Stalker I

Mining and treatment of gold ore in the Ashanti region at Obuasi, Ghana has been continuous for more than 100 years. Earlier production from this world class deposit can be traced far into the history of West Africa's gold trade. As part of a general development and expansion program, Ashanti Goldfields Corporation (Ghana) recently undertook a program to heap leach oxidized near surface ore. Kappes, Cassiday & Associates was given a major role in the design, equipment supply, installation and start-up management of the 3000 tonne/day heap leach. Unusual conditions included a high annual rainfall and an ore which could be characterized as a soft, decomposed, water saturated schist. Production began in March 1990. Startup problems and their solutions are discussed.

Jan 1, 1991

The inauguration of a geological department for the mines of North Broken Hill Limited necessitated the provision of accurate plans and sections upon which geological facts and projections might be plotted.Unfortunately, the basic data were very inadequate. For the British Section, sill survey plans were available, but no regular stope plans. Filling surveys had been preserved for many stopes, but on innumerable pieces of tracing linen, without heights of any kind, and not altogether reliable (as indicated by the finding of very inconsistent duplicates). For the bulk of the old stopes no plans exist at all. The expenditure of much time and patience has resulted in the co-ordination of most of the existing stope data, but the British Section must for the rest of its life continue to have surprises in store, as has been the case for many years past. Manufacture and preservation of stope records has, of course, been on a sound footing during recent years. No reliable cross-sections of the British Section were available.The Marsh, Junction, and Junction North Sections have for the most part very poor data. In the North Section, level plans were fairly reliable, and cross sections of the lode made for ore reserve purposes have been preserved for quite a few years. No floor plans of stopes were kept, however, until a couple of years ago.Diamond Drill records vary in quality. Practically none exist for the Junction and Junction North Sections. Logs have been kept for the British Section drill holes, but are...

Jan 1, 1940

The emergence of a new range of database communication standards and software has provided the impetus for the development of a new approach to exploration and mining data management. The acQuire software produced by acQuire Software Pty

Jan 1, 1998

During the 20th century, the iron ore mining industries of Canada and the United States passed through several periods of transformation. The beginning of the 21st century has seen yet another period of transformation, with the economic failure of a number of steel companies, the acquisition of their facilities by more viable steelmakers, and the consolidation of control within the North American iron ore industry. Changes in Canadian and United States iron ore production and the market control structure involved are analysed. The consolidation of ownership, formation of foreign joint ventures within North America, planned divestitures of upstream activities by steelmakers, and industry changes made to ensure availability of feedstocks will be reviewed. The traditional isolation of the Canadian and United States iron ore operations and their strong linkage to downstream steel production will be discussed in the context of a changing global economy. Management-labour conflicts that have taken place and agreements made during 2000 through 2004 will be discussed in the context of the economic environment leading up to these agreements. Cooperative agreements between competing Canadian and United States companies to resolve client needs in processing and blending will be examined. A joint industry-government project designed to use new technology to produce direct reduced iron nuggets of 96 - 98 per cent iron content using non-coking coals will also be assessed. Changes in iron ore transportation methods, ownership and infrastructure will be reviewed for both rail and inland waterway transport between Canadian and United States companies. A brief analysis of social and environmental issues relating to sustainable development of the Canadian-United States iron ore industry will be included.

Jan 1, 2005

By Bartrop S. B

Mount Isa mine has a long history of successful exploration since discovery 70 years ago. Remaining reserves, although substantial, exist in a scheduling framework which involves long-term production from new ore sources with attendant technical risk and major capital investment. Current exploration aims to incrementally increase reserve tonnage to maintain existing production levels as well as to provide a buffer for potential start-up delays from new ore sources. Exploration also aims to increase the net present value of the operation by discovering new major orebodies around the Mount Isa and Hilton mines.

Jan 1, 1993

The central thickened discharge system of tailings disposal takes advantage of the natural beach slope formed by sub-aerially discharged tailings, and the non-segregating properties of thickened tailings, to create a homogeneous conical stack. The need for containing embankments can be largely avoided leading to capital and operating cost savings. Methods for estimating beach slopes and tailings density, essential parameters for the design of such a system, are described. Case histories from three mining operations are used to illustrate the application of the technique, There are also seen to be potential advantages in the areas of water management, seepage, and rehabilitation. Laboratory and in-situ testing enable parameters to be determined.

Jan 1, 1991

When a major mineral find has been announced the general perception is that a battle between Aborigines and the mining company involved will inevitably occur.It is a fact that many miners in the past have not had a good relationship with Aborigines because of their indifferent attitudes towards them. They saw no common future and went their particular way. However, attitudes have changed significantly since Noonkanbah and both miners and Aborigines are seeking common ground in order to achieve mutual benefits from the establishment of a mine on or near Aboriginal land. There are many obstacles that both miners and Aborigines need to overcome inordertofindthiscommongroundtoachieveawin/win situation. The obstacles can be found in entrenched ideas and practices which need overhauling, not the least of which emanate from government policy and requirements.Without going into specifics, the Noonkanbah incident during the 1970's where Aborigines and their supporters confronted miners who were ordered by the Western Australian governmentto drill on Aboriginal land, polarized Aborigines and miners. Since this incident, many Aborigines, particularly those in the cities, have had the attitude that mining and Aboriginal culture are in direct conflict. Aboriginal opinion is generally shaped in the larger cities through mass media coverage of the opinions of urban Aborigines and their supporters. Through no fault of their own, these Aborigines were removedfromthe land of their ancestors and have notlived atraditional Aboriginal life-style for a number of generations and most have little knowledge of, nor have had involvement in, traditional Aboriginal lore and culture. For the most part these people live in awestern life-style and few still know their language. They generally have high profiles, often giving viewpoints that are wrongly considered "Aboriginal" and supposedly representing all Aborigines. This group is very different with their thought processes and values from those Aborigines who live on their own traditional lands with a traditional life-style, and practise their age old ceremonies. Their tribal values are based in their relationship with the land, expressed through complex religious ceremonial rites of song, dance and legend. Today this group is very much diminished in numbers but nevertheless in the region of the Gulf of Carpentaria there is a high proportion ofpeople who practise their lore, speak their own languages and pass on traditions to their children. It is well documented in the history of Australia that Aborigines have been decimated in numbers and whole tribes have been wiped out. Certainly in this region the experience has been no different.

Jan 1, 1993

Successful restoration of Ballarat region alluvial gold workings to Box-Ironbark forest requires realistic evaluation of techniques. A stocking level threshold of 68 percent is used to rate the success of 'broadcast' seeding of E. microcarpa, E. Melliodora and E. Leucoxylon.Failure necessitates follow-up enrichment planting with tubestock, which is considered undesirable, interalia, due to pathogen, spacing and economic problems.

Jan 1, 1992