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The papers to be presented in this Session show an interesting range of subject matter. Three discuss specific problems associated with existing mines, one deals with hydrogeological risk evaluation and one uses the impact of mine drainage on an aquifer to analyse a large-scale hydraulic parameter. Paper 1. Environment studies to determine the impacts of re-opening Banska Stiavnica-Hodrusa ore district in Czechoslovakia - Dusan Cababla - Marian Skaviniak. Future developments in established mining areas may have significant hydrogeological implications, especially where the existing mines are to be deepened. In turn this may have an impact in the area of the disposal of ever larger quantities of mine water, particularly, as is often the case, where the quality of this water is poor.

Jan 1, 1988

By A Hollonds, R Young

High commodity prices have produced a boom in project expansions and growth projects. Unfortunately, some of the early results have been poor, with some projects suffering considerable cost growth, project delays and start-up problems. The cost growth experienced in some projects is well beyond just escalation, but suggests weaknesses in the development of feasibility studies. Independent project analysis (IPA) has developed a large database containing information on project outcomes in the minerals and metals sector, and has identified, through its front-end loading (FEL) index and team development index (TDI), some key leading indicators of project success and project problems. This paper highlights key areas of weakness in feasibility studies that have driven poor project results, and the best practices that have driven improved project results.

Jan 1, 2009

I have the pleasure to present 6 excellent papers in this section all of major relevance to the mining environment of today where competing social, legal and monetary interests and their often complex interaction require serious consideration. This is particularly true today where huge fluctuations in commodity prices makes mining a perilous undertaking while the world increasingly are becoming aware of the serious threat that mans activities has on his environment. The 6 papers deal with such complex issues as safety in an underground environment; How to protect sensitive wetlands well into the next century; The enormeous waterproblems in China and conflicting dewatering/water supply needs; Disposal of contaminated water in sensitive areas and the dynamic interaction between mining companies and legislation.

Jan 1, 1988

The Australian mining industry has suffered from a decline in its public image during the past decade. This has occurred partly as a result of increased questioning of accepted social and economic values since the mid-1960s and the greater restrictions placed on industry since then, and partly ò from the industry's inability to effectively answer its critics. Public opinion surveys have shown the depth of the decline in the industry's community acceptability and highlighted those issues which people regard as disadvantages of mining. The industry's poor public image has contributed to the difficulties of attracting young people to take up professional careers in mining. All those involved in the industry have a responsibility to assist in activities designed to improve the industry community Acceptability.

Jan 1, 1981

By B J. van Loggerenberg

The capital cost of major items of mining equipment is very high. The operating cost of such equipment is also high. It is therefore important that such expensive equipment is used productively. To this end mine management uses production data systems and management accounting systems to monitor events and provide data for analysis to enable management to make operating and business optimisation decisions. This could be done better if there was an understanding of productivity in terms of its utilisation and efficiency components. What has been missing has been a methodology to properly account for the productivity of equipment in terms of its contribution in dollars to the costs and profit of the mine. An explanation of the Productivity Accounting methodology will be given. It will then be shown that productivity has two components, that of capacity utilisation and efficiency. These are defined and the dollar contribution of each to costs and profit shown. The efficiency component tracks the effect of proportional changes in input cost quantities used in the mining process as mining production changes. The capacity utilisation component tracks the effect of step changes in the input cost quantities used in the mining process as mining production changes.

Jan 1, 2003

By Bowmaker MD

Zinc and lead sulphide flotation con centrates containing from 0.02 to 0.20% Cd are roasted on an updraught sinter machine at the Cockle Creek Works of Sulphide Corp- oration Pty. Limited to provide sinter for simultaneous smelting of zinc and lead in an Imperial Smelting Furnace (I.S.F.). The major portion (about 85%) of cad- mium in concentrate feed to the Sinter Plant is eliminated with sinter fume and is rec- overed by weak acid leaching in the Cadmium Plant'followed by counter-current decantat- ion, ion exchange concentration, precipitat- ion of cadmium sponge and partial refining to caustic refined cadmium metal. Cadmium not eliminated during sintering is volatilised in the I.S.F. and subsequently recovered as zinc alloy by distillation in the zinc ref- ining columns of the Zinc Refluxer. The partially refined cadmium metal and cadmium- zinc alloy are blended as feed to the cadm- ium refining column where separation and recovery of cadmium is effected. Condensate from the column is further refined under caustic soda flux and cast into anode shapes. Production is 200 t.p.a. at 85% recovery of cadmium in concentrates. Emphasis is placed on changes from the practice described by Baker and Munro (1965) and upon operation

Jan 1, 1972

By Keys NJ

The so-called COMAT process provides a method for leaching low grade sulphide mattes in an acidic ferric sulphate medium in such a way that non ferrous base metals such as Ni,Cu and Co are substantially all dissolved; the concentration of residual acid and dissolved iron remaining in the leaching solution is low, and a large portion of the sulphide sulphur is converted to elemental sulphur. Thus the quantity of neutralising agents required to remove residual acid and dissolved iron from the leach solution prior to subsequent recovery of the dissolved base metals is greatly reduced. The leach residue and iron precip- itate report in a readily filterable form. In this paper results obtained on a pilot plant scale are presented for the leaching of a typical low grade matte in the manner describ- ed above; for the solvent extraction and elec- trowinning of copper, and for the removal of residual acid, copper and iron from the copper solvent extraction raffinate. Processes tested on a laboratory scale for the further recovery of cobalt and nickel by solvent extraction and electrowinning, and for the recovery of sulphuric acid and ammonium hydr- oxide from the dissolved ammonium sulphate salt contained in the final plant effluent, are also briefly described.

Jan 1, 1986

COAL constitutes such a gigantic item in modern industry, either for direct heating, production of coke for smelting, or for the generation of power, that its quality and price play a very significant part in economic industrial progress. Australia is still a very young country industrially, and is groaning under many disabilities compared with competitors overseas, not the least of which is the quality of coal. Linked with the word "quality" should be that of "utility," for high-ash content prevents efficient utilization of the fuel.The marketing of good quality coal is a very important matter indeed, and if industry in Australia is to progress in the way that it should, this matter must receive keen attention.New South Wales, above all the other Australian States, has been blessed by nature with vast coal-fields, from which fuel is shipped to every State, and provides the base for power for most of our railroads and industries.Experts frequently refer to the fact that in some districts only partial extraction of thick seam coal is being made, without a care or thought for the future. Ranking next in importance to this is the fact that much of the coal is being carelessly marketed.Very few collieries in Australia are equipped with coal-washing plants for dealing more particularly with small coal grading which most industries require, and to which coal producers as a whole pay the least attention. In England each year nearly20,000,000 tons of coal is being water-washed before sale, and is marketed as a fuel of far greater utility once it has been freed from extraneous ash.Investigation proves that a great many pits in New South Wales are marketing coal (more particularly small coal) containing a considerable quantity of extraneous ash, due to the admixture...

Jan 1, 1926

By D Smith, D Reid, D Bradshaw, C Brough

The Merensky Reef at Northam Platinum Mine in South Africa is characterised by a high degree of variability with respect to reef elevation (difficult to mine), as well as mineralogy and texture (difficult to process). Development along strike and down dip of multiple reef types has led to unpredictable run-of-mine characteristics that pose problems for the mineral processing circuit at Northam. Following mining terminology, Normal, Transitional (NP2) and Pothole (P2) Merensky reef types can be defined, and this geometallurgical study aims to characterise and understand the relationship between their mineralogical characteristics and laboratory scale batch flotation performance. The plagioclase-rich NP2 reef ore is the easiest ore to process in terms of capacity for high mill throughput as well as flotation performance. The lack of very fine-grained disseminated sulfide textures in the NP2 reef ore results in better liberation characteristics relative to the Normal and P2 reef types. Consequently, chalcopyrite, pentlandite and sulfide recoveries are highest for the NP2 reef ore. The lack of ferromagnesian minerals in the NP2 reef ore also results in the recovery of the least amount of floatable gangue during flotation tests. The Normal and P2 reef ores are similar to each other, with an orthopyroxene-rich mineralogy with associated alteration minerals. The P2 reef is also characterised by the highest sulfide content and degree of pentlandite liberation. Chalcopyrite, pentlandite and pyrrhotite liberation is only significantly increased by a change in grind for the Normal reef ore. The change in grind, however, only significantly affects pentlandite flotation performance and overall froth stability for the Normal reef ore. However, for all three ores, a small change in grind has a detrimental effect on pentlandite flotation performance.

Jan 1, 2008

The B.H.P Company has been using shortwall mining methods for the past six years in the Southern Field. several aspects this experience shortwall equipm H.P. Company has been using shortwall mining methods for the past Northern Collieries and for several years at Corrimal in the Various papers have described and assessed that work. There are of recent work which supplement prior publications. The summary of to date is a background to discussion of the role of self-advancing ent in support in pillar extraction.

Jan 1, 1974

By Fuerstenau MC

Zinc cementation and carbon adsorption are both presently used for precious metals recovery from cyanide leach solutions. Each of these techniques exhibits unique processing features which renders them suitable to treat solutions with different properties and in different applications. In this study, the two processes are reviewed and compared. Operating data from a number of Merrill-Crowe precipitation and carbon adsorption plants in North America have been obtained and used in this analysis. The relative capital and operating costs for the two processes have also been considered.

Jan 1, 1993

New knowledge has no economic value unless it can be applied, or æcapturedÆ, as the R&D jargon has it. Australia probably spends more than $500 m per year on mineral industry R&D, distributed amongst the mining companies (IR&D Board, 1997), CSIRO, the universities and others. The investors in this research (industry, and the community via government) will expect some sort of return from their investment. The return will be poor unless the know-how developed in R&D programs can be exploited. This paper explores some of the issues involved in capturing the outcomes of mineral industry R&D in a form which can be exploited for economic benefit, and suggests ways in which it might be done better. It is based on the experience of the JKMRC in conducting applied research in mining and mineral processing and delivering it to the industry. It may seem presumptuous for a research contractor to be telling its clients how to do their job. However, the process of developing, acquiring and implementing R&D outcomes has to be a partnership between provider and receiver, in order for this process to work efficiently. This applies whether the two parties operate within a single corporation (a corporate laboratory and a business unit, for example) or are two entirely independent organisations (eg a mining company and a university). Both partners have a role to play, and the best examples of realising the benefits of R&D almost always involve the open-hearted and skilful handling of this synergy.

Jan 1, 1998

By B Leyland

The media in Australia is currently rife with articles and pronouncements on global warming as the most significant crisis of our time, which may æthreaten the future of civilisation as we know itÆ. This has been recently reinforced by release of Al GoreÆs film æAn Inconvenient TruthÆ, and one would be led to believe that the science of global warming is settled. And yet there is a strong body of literature disputing this apparent consensus which suggests that care should be exercised in introducing radical policies to solve a crisis which may not be real. Such policies would have a major impact on those in professions such as engineering (project approvals and design to minimise greenhouse gas emissions), accounting (carbon tax issues) and the law (corporate disputes on greenhouse gas issues are already in train in the USA). This paper addresses the hysteria apparent in the climate change debate by presenting factual evidence relating to climate change and the current phase of mild global warming. Some of the more extreme statements on future impacts are repudiated with published data, and alternatives to the purported role of fossil fuels in temperature change are offered. The potential impact of political decisions on professional activity is discussed, as are the implications of a possible future reversal of the scientific consensus, as has occurred in the past. The paper concludes with a call for the professions to exercise their Learned Society role to ensure that a rational and public debate is held on the broad issue of climate change.

Jan 1, 2007

By Enichlmayr E

Lignin grouts are cheap and easy to get. They have some desirable properties, but they aag less used now because environmental pollution is often caused by Cr from the lignochrome component of the grout. Their usefulness was researched in an earlier paper on lignin as a grout from other viewpoints. A non-toxic grout FUL was made composed of furfural, urea and lignin. After initial tests, including tests by spinning regression design, some response equations in which FUL's properties are described were obtained. Optimum formulations have been established by using optimization methods based on response equations. The engineering quality was assured by formulations whose properties were measured in further tests. The mechanical feature of gelling sand was measured by means of triaxial tests. This provides a basis for using FUL grout in-situ. Finally, an in-situ experiment on FUL was completed successfully. The results were that cracks in stratum were filled or blocked, the gelling of FUL had high strength, and low permeability and consolidation were achieved.

Jan 1, 1988

The technological advancement in computing power and the increasing demand for information processing systems spread throughout many aspects of a corporation's business activities has revolutionised management information systems departments. This revolution is manifest in the proliferation of mini-computers and micro-processors as well as the planned or unplanned migration from centralised processing to distributed processing. The total data processing investment in people, hardware, software and telecommunications has reached a high level in many organisations. Therefore, the cost of inadequate planning or ad hoc growth of systems can be considerable. The concept of MIS systems planning has gained adherence in recent years; however, there appears to be a wide diversity in the effectiveness and quality of corporate systems plans. To be effective a systems plan must have the support and concurrence of executive management of an organisation. A disciplined planning approach to systems together ,with the involvement of senior user management as well as MIS management is necessary to develop a satisfactory systems plan that forms the basis of a corporation's data processing strategy.

Jan 1, 1980

Since 1960, the Dongchuan Copper Mining Bureau, Yunnan Province, China, has treated copper oxidised ores by sulphidisation - flotation technique only to recover copper. In order to improve the metallurgical performances and economics of flotation, extensive development work has been carried out during the past 30 years: several specific flotation flowsheets have evolved from the originally selected `stage - grinding and stage - flotation' flowsheet to suit various ores; the overall grinding size of the ores has been increased from 80 per cent - 200 mesh to 90 per cent - 200 mesh, resulting in significant increase in copper recovery; the substitution of CaS for NazS proved to be successful in sulphidisation of copper oxidised minerals, and also in avoiding the depressing effect of Na2S on copper sulphide minerals; the application of a number of activators of copper oxidised minerals, especially ethylene diamine phosphate, has considerably improved the flotation performance and decreased the consumptions of other reagents. Finally, the combined use of sodium hydroximate with butyl xanthate has been shown to be effective in enhancing the floatability of both copper oxidised and sulphide minerals.

Jan 1, 1993

By P D. Williams

The Phoenix mine is one of NewmontÆs open-pit operations located in Nevada. Mining started in 2005, with the mine producing gold, copper and silver. The mine life is about 20 years. The gold grade estimation uses the Newmont in-house indicator kriging approach to handle the high variability in drill hole composite grades and support mining selectivity. Each block contains up to 200 subblocks with different gold grades. A flotation mill is designed to process oxide and sulfide ores, recovering gold, copper, and silver. An additional copper leach process is currently under study to process low gold and high copper oxide material with low copper recovery in the mill. The metallurgical recoveries and processing costs are dependent on many variables including rock formation, metallurgical domain, cyanide soluble copper and sulfide contents. This paper describes the Newmont in-house indicator kriging procedures and the revenue based mine planning software system implemented at Phoenix mine to address the complexity resulting from multi-process, multi-metal and indicator kriging model.

Jan 1, 2007

Exploration for uranium in Australia has so far discovered reserves equal to 17.5% of the Western World's. The Australian uranium industry, when fully developed, will be one of the largest producers and possibly the largest exporter in the world. The world's nuclear industry is young, rapidly developing in size and technology and is subject to more social, political and regulatory controls than any other industry. This paper considers the probable development of Australia's uranium industry against a background of normal commercial parameters together with other factors which are peculiar to the nuclear industry. As the theme of this conference is "Australia's role in the World Mineral Indus- try" this paper concentrates on the commercial and practical aspects associated with the development of Australia's uranium resources in a world context.

Jan 1, 1979

Blasting is at first sight a simple operation. Blastholes are drilled in a suitable pattern, primed, charged with explosives, stemmed and finally the blastholes are connected together to give the appro- priate initiation sequence. In practice the action of the explosive takes place in the interior of an opaque rock mass and only the external faces of the rock mass to be blasted can be easily observed. The mechanisms of blasting cannot be observed directly and must be inferred from observations of the free face and meas- urements of particle movement made by sensors grouted into holes in the rock. Explosives react very rapidly, in some microse- conds and any instrumentation of a blast must have an appro- priate response time. In many mines several rock types can be encountered during production. Several different methods of blasting may be necessary to cope with changes in rock types espe- cially if weak rocks are found in the final limits. This also makes it difficult to be sure of getting a large enough volume of rock to perform a series of reproducible experiments. While there appears to be agreement on the mechanism of blasting it is unlikely that a detailed understanding of how all the variables that can be encountered in practice affect blasting. The ease of assessment of the results of blasting depends on the criteria used. It is easy to isolate, measure and count over- size boulders. It is however difficult and costly to get a complete fragment size distribution. Methods used to assess blasting can vary significantly from site to site and the ways in which data are collected, presented and analysed will vary making compari- son of blasts at several locations very difficult. The definition of an optimum blast can also vary with the type of blasting. The muck-pile profile and fragmentation will be different for a dragline to that for a truck and shovel operation. In order to be able to assess blasting the mechanism has to be understood. Th rock and explosive properties considered rele- vant to blasting can then be determined. This paper discusses the generally accepted mechanism of blasting. The on-site observa- tions to assess blasting are-then listed. The mechanism of blast- ing can also be modelled and the use of modelling to optimize hlaetina ie thPn Aiernccarl

Jan 1, 1988

Since the 1970s we have seen a marked corporate response in terms of the environment. In part this has come from regulation but it has largely come from stakeholders and the community. We now see a similar trend towards sustainability. The Brundtland (1987) definition of sustainable development provides a direction for advocates: the advance of human prosperity in a way that does not compromise the potential prosperity and quality of life for future generations. In my view its three essential components are: economic, environmental and community. The Global Mining Initiative and the contributions to the Rio World Summit and the Johannesburg World Summit on Sustainable Development indicate that sustainability is being taken very seriously by the mining industry. But does the minerals industry really embrace sustainability as they claim? There is a view that in reality sustainability is a non-event and that the triple-bottom line approach is only a convenient catch-cry for companies who are actually focussed very strongly on the economics part of the equation. Chemical engineers are showing a strong trend to more sustainable practices and the chemical industry has shown real commitment to research into developing sustainable processing systems. This requires a framework for thinking and design and the chemical industry is demonstrating true innovation as it moves towards æno wasteÆ technologies. Whilst there are limits to the rates of change that can occur the minerals industry should also be moving in a much more determined manner towards the notion of processing of products designed for whole-of-life cycle û with minimum/no waste. But is the minerals industry just paying lip service to the importance of research to sustainability?Several common themes influence the science and innovation agenda in Australia, which will affect the development and adoption of innovations by AustraliaÆs minerals sector. First is the well-proven link between peer-reviewed scientific excellence and commercial application. Second is the rise of multi-disciplinary Mode 2 research, which has developed in response to the complexity of problems faced by contemporary researchers, which are best analysed by combining expertise from two or more disciplines. Successful innovation outcomes, in any field, including minerals processing, is promoted by Mode 2 research which benefits from greater levels of networking and collaboration. Kofi Annan in his Message to the World Social Forum puts it very succinctly æThe way forward lies in finding constructive solutions togetherÆ.

Jan 1, 2004