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The major slime forming minerals in coal seams are generally montmorillonite, illite and kaolinite, and due to the consistant trend to full seam mechanisation in New South Wales and Queensland these minerals remain in the feed to a coal preparation plant. After coming into contact with water their size degradation is very rapid, and therefore they mostly report to the fine coal cleaning section of the plant. Froth flotation, being the most effective method of beneficiating fine coal, is widely practised in these two major coal producing states of Australia. Plant experience and laboratory tests suggest that the presence of these slimes in the flotation circuit depresses the flotation of fine coal. Although the deleterious effects of slimes on the flotation behaviour of minerals is well known, the mode of their adsorption at the mineral surface has been a subject of controversy for some time. In this paper, on the basis of the surface properties of slime forming minerals and coal, a model has been put forward to explain the adsorption of slimes at the coal surface. The degree of slime coating has been examined by scanning electron microscopy. Laboratory tests have revealed that with the appropriate use of polyvalent phosphate electrolytes these slimes can be liberated from the coal surface. Just attrition and desliming are not enough to ensure complete liberation of slimes. Coal, after treatment with these electrolytes and then deslimed, floats readily with a common frother, such as MIBC. Modifications in the conventional flotation circuits have been suggested to ensure an efficient flotation of fine coal.

Jan 1, 1978

Industrial relations on Australian and New Zealand resource projects can be volatile. Therefore investors have become increasingly aware over the years that sound industrial relations during construction is vital to the overall success of their project. There has been a wide range of actual industrial relations performance, project by project, and the degree. of success often directly correlates with the degree and thoroughness of pre-project planning. However, although many projects have been crippled by delays and cost overruns because of labour disputes, good results are achievable. Total commitment to the project by all parties involved is essential and it is up to the employers to seek out this commitment and not just trust mother luck. Industrial relations must be taken very seriously as the price of failure can render a resource project unviable.

Jan 1, 1983

The current insurance market has been brought about by a number of pressures, including: collapsing investment returns; growing losses, both normal and catastrophic; and reserve strengthening. This is impacting most classes of insurance coverage, with the traditional characteristics of higher pricing and greater levels of retention, however it is now translating into a lack of capacity and reduced coverage. This presentation will explain how the market has arrived at this situation and will challenge whether this is the traditional insurance cycle or a structural correction. It will also address the anticipated time of correction.

Jan 1, 2003

South Africa is the world's largest producer of gold. The survival of its gold mining industry is dependent, to a large extent, on the successful implementation of new mining technology which reduces the operating costs. Gold mines of the country have a record of a high operational cost per tonne of rock excavated. The geology of the gold-bearing rock, in addition to the mining depth and the gold recoverable grade, profoundly affect the profitability of the industry. Among the other mining operations, drilling and blasting take a fair share of the mining cost. It is therefore proper to implement a dynamic approach of technological review aimed at combating the escalation of mining costs. Over the years, the industry has moved away from labour intensive activities. Mechanised operations are introduced where possible. Management techniques are oriented more towards better utilisation of human resources and machinery so as to enhance productivity in the stopes. This paper addresses the issue with particular reference to blasting operations in the stopes of deep gold mines. It reviews the conventional drilling and blasting techniques. It outlines some innovative changes brought about in the course of recent years with the aim of optimising productivity and the stope efficiency in particular. It focusses on the peculiarities of the blasting technology in deep mines. It discusses the issue of interaction between the high stress fields underground and the blasting generated stresses on rock fragmentation, as well as their impact on the remaining excavations. It anticipates the concept of the new technology of selective blasting in stoping. Finally it puts forward the crucial role played by management of the human factor underground.

Jan 1, 1995

By Hughes CA

The need to recover metals from low grade deposits, old tailings, etc., combined with improvements in equipment design and the development of new extractants, has resulted in solvent extraction (SX) metal recovery reaching new importance (Webster & Ferron, 1993). The basic principle of solvent extraction is the use of an equilibrium system in which a metal ion is transferred from an aqueous phase into an organic phase, (Equation 1), (Ritcey, 1984). M + E ME . (1) The organic extractant (E) is usually specific for a certain metal ion (M) and forms a metal complex in the organic phase, leaving the impurities behind in the aqueous phase. To recover the metal, the equilibrium is reversed and the metal ion is transferred back from the organic to another aqueous phase in a process called stripping. The metal is then recovered from the aqueous strip solution, usually by electrowinning.

Jan 1, 1990

By Spencer PA, Winborne DA

The Porgera mineral deposit in Papua-New Guinea contains gold as finely divided, probably submicroscopic (1 um) particles dispersed in a pyrite sulphide matrix. Only 25-30% of the gold in pyrite can be extracted by direct cyanide leaching and fine grinding the pyrite does not increase gold extraction significantly. This work is concerned with the application of alkaline leaching at atmospheric pressure to oxidise the pyrite prior to gold recovery by cyanidation. The paper presents and discusses results of a comprehensive set of testwork using sodium carbonate, sodium hydroxide and calcium hydroxide alkaline media. Best results, at 60-70% gold extraction, were obtained with sodium hydroxide systems.

Jan 1, 1984

By Watkins JR

The educational system is a dynamic; a flow resource that can be significantly shaped, changed and - refined by educationists. This paper analyses these various facets of geo- science education in Australia. The Australian educational philosophy is essentially a laissez- faire model, a free market approach without any real government or professional directive or stratagem. Students are therefore free to choose their own educational pathway dependent only upon their ability and the access to courses. Geological education at the tertiary level in Australia is described and critically analysed. There is a real need for a rationalisation of geological education in Australia, and this rationalisation should include not only the number of courses offered but should also aim to fully define both the philosophy and purpose of geological education and the accreditation procedures for the Students.

Jan 1, 1986

The Nelson province was chosen as the prime area for rhenium sampling, based on its mineral associations. Sample preparation involved benefication by grinding and flotation. A modification of published procedures for rhenium analysis was developed and the results compared with those obtained for molybdenum on the same samples using atomic absorption spectroscopy. The results of the analysis for both metals is discussed and the relationships between rhenium and the molybdenum mineralisation of this region is commented on. A metallogenic province is defined for molybdenum and rhenium and the tectonic setting for this is discussed. Some consideration has been given to rhenium possibilities in Fiordland and the Coromandel Range.

Jan 1, 1980

By B Cooper

During the design of a new production facility for a greenfields or significant brownfields expansion many design decisions are made driven by an unquestioning objective to achieve 'lowest cash-cost' production costs. In many cases this translates to a design and operating philosophy based on largest-available, single-line equipment. Although acknowledged as an approach that is efficient from an operating cost perspective does this approach always maximise shareholder value? There is an increasing awareness in the mining industry of the value of project flexibility, robustness and value options. The design of a new production facility creates a window of opportunity which should be structured to ensure that project value options and robustness are understood and exploited. This requires the use of emerging valuation methodologies, such as Value-at-Risk and Real Options, as well as tried and trusted NPV/IRR approaches. The paper provides an overview of the basis and application of these less well known techniques in the context of metallurgical plant design. Design guidelines that demonstrate how value options and flexibility can be quantified from both a risk and value perspective are presented. Issues such as use of single versus multiple line equipment, optimum cut-off grade and improved exploitation of the inherent variability of the orebody are also examined. Finally the management issues and approaches to achieving this will be briefly discussed; for example it is common during project development to drive towards increasing certainty as rapidly as possible to facilitate 'accurate' estimation of costs. Understanding and exploiting value options requires a project culture that tolerates, and revels in, ambiguity and uncertainty û something that would make many project teams uncomfortable!

Jan 1, 2008

By D R. Swinbourne

In the recent past a number of smelting plants were commissioned in India to supply the rising demand by domestic steelworks for manganese-based ferroalloys, and they enjoyed cheap electric power and readily available high-grade manganese ore. Presently, the cost of electric power is much higher than in some neighbouring countries, there continues to be poor transport infrastructure and the prices of high-grade manganese ore have increased. Additionally, the Indian Government has opened its economy to the outside world, resulting in the import duties on ferroalloys being drastically reduced. In this paper the current situation in India will be detailed, the electric arc furnace and blast furnace smelting methods for ferroalloys compared and proposals for the construction of a new ferromanganese blast furnace in India outlined. The future of ferroalloy smelters in India will be assessed and actions which could be taken to improve their position discussed.

Jan 1, 2000

By Mendeckl A. J

Anglo American Corporation has always viewed technological development as vital and as such has placed research and the implementation of new technological practices high on its priority list. Support is given to a number of research institutes but a significant degree of reliance is placed on in-house research carried out at individual companies and at the Group's main laboratory complexes. The Corporation's interests are diverse with advanced practices and innovative technology ranging from new battery technology with wide application to deep level shaft technology with very specific application. In this paper, we aim to concentrate on a particular system developed primarily for use in seismically active deep mines. The system has proved to have far wider application and has the potential to be further enhanced to meet the needs of users across a broad range within the industry and even beyond. As the nature of this conference is to inform delegates of advanced mining practices, we should simply mention that we could have talked on subjects relating to the advances made in deep level winding technology including winder drive and brake control to alleviate dynamic rope loads, shaft steel design for high pay load high speed winding and shaft safety systems such as slack rope devices and moving lip loading facilities to cater for rope stretch. Other areas of interest relating to refrigeration using ice technology or non-explosive rock cutting using diamond wire or saw technology could also have been of interest. As the South African gold mines become deeper and the problems associated with depth become more acute, answers had to be found and systems developed to cope with very high rock stress and the related seismicity. The fundamental understanding of the behaviour of the rock mass has always been important but became critical on our mines to ensure the safe extraction of the orebody. Basic research into and the application of physics, applied mathematics, seismology, rock mechanics, electronics and computer technology have helped us to develop the Integrated Seismic System - Integrated because of the system's abilty to monitor seismic and non-seismic sensors simultaneously and because it encompasses data acquisition, processing and interpretation into one system. The system which is in use at all our gold mines has found application not only in South Africa but also in such locations as Australia, Chile, Canada, Europe and Japan. A highly motivated team of scientists under the leadership of Aleksander Mendecki developed the majority of the hardware and software needed for the system. In essence, the system allows us real time monitoring of energy release and stress transfer data that with the aid of modern computers is turned into useful information. The information so obtained has allowed us to improve our mine and extraction designs to minimise the inherent hazards. The system has proved to be an extremely useful management tool as substantiated by the demand for the product. The paper is intended to convey to the reader the technical concepts and the presentation is intended to demonstrate the usefulness of the system.

Jan 1, 1995

Staff turnover percentages on projects in the minerals sector are at levels that would not be accepted in business less than five years ago. While this is being driven in part by the shortage in skills to service the industry there are underlying factors, beyond the increases in remuneration, adding to the turnover. Having identified the five major reasons why people do not stay, this paper confirms that leaders and the various styles are common to all companies. The paper comments briefly on these major reasons and suggests the problem is firmly with management. It also offers possible remedies to reduce the attrition and therefore improve the opportunities for a quality project evaluation.

Jan 1, 2009

Government geoscience may be categorised by objective under three headings: Applied Research for Geoscientific Framework Studies, Resource Inventory, and Technical Advice. In Queensland, the Department of Resource Industries is active in all three categories. Under the program-based management system adopted in 1987, three Programs, namely, Geological Survey, Mineral Resources Development, and Energy Resources Development and Utilisation, have geoscience responsibilities.Prime responsibility for geoscience resides with the Geological Survey Program, which provides a geoscientific framework for mineral and energy exploration and the development of the State. Simply stated, the Program goal is to provide geological information when and where it is required. Geological Survey work also encompasses aspects of resource inventory and technical advice, complementing the work of the other two Programs. This role has a 122 year long tradition, for geoscientists of the Geological Survey have been engaged in investigations designed to facilitate the identification and utilisation of the mineral, water and energy resources of Queensland since 1868.

Jan 1, 1990

The efficient design of carbon-in-pulp (C.I.P.) plants involves the integration of both process engineering and design engineering.Many recently constructed plants have not recognised the above interrelationship, and as such have incurred higher capital and operating costs than were in reality necessary. This has been compounded in some cases by slavishly following the design of plants where process conditions are different for the ore characteristics in question, thus perpetuating design errors that finally become industry "accepted practice".In the paper that is to be presented the unit operations of crushing, grinding, classification, leaching, adsorption, desorption and electrowinning in C.I.P. plants will be discussed with reference to the integration of process and design engineering.

Jan 1, 1986

Over the past 5 years, Bougainville Copper Limited has undertaken a number of major plant expansions to the copper concen- trate production plant at Bougainville in the North Solomons Province of Papua New Guinea. These projects have scheduled three additional ball mills, three new banks of Outokumpu flotation cells, four additional tertiary screens, two additional tertiary crushers, and more recently four high capacity 24.5m dia. tailing thickeners. The value of the five separate projects totalled more than A$100 million. A requirement of commissioning and bringing on line of each of these projects has been to minimise both operational losses and copper concentrate production. The commissioning has been successfully implemented by detailed planning of the commissioning work in conjunction with the plant operation. Planning has been detailed for each man involved on an hourly basis, highlighting the work required on each commissioning task that is to be undertaken and the time expected to achieve activity Completion.

Jan 1, 1986

The known coal resources of South Australia are either of poor quality, or expensive to extract, or both. Export quality coal occurs only at great depth in the remote north of the State; the balance of the State's coal resources are suitable only for local electricity generation. Currently there is only one coal mine in the State, at Leigh Creek. This provides fuel for approximately 34% of the State's electricity generation, the balance being fuelled by natural gas. In the near future, new fuel sources must be developed to augment diminishing supplies of natural gas, and to cater for increasing demands for electricity. The South Australian Government has determined that future electricity generation will be based on the combustion of local coals. The geological and geographical environment of the known coal deposits and the quality of these coals are such that the most up to date and innovative technology must be applied to both extraction and combustion processes. The Government, the Electricity Trust of South Australia, and several Australian and overseas companies have embarked on an extensive research and development programme to ensure that these otherwise useless resources can be developed to the benefit of the State.

Jan 1, 1987

The introduction of rubber tyred diesel equipment underground in the early 1960's and subsequent design improvements to diesel haulage systems over the past 2 decades has meant that diesel truck haulage has often been the first choice when selecting a haulage system for a new underground mine. Even today only 9% of all vehicles underground are electric powered.However, with the development of more efficient electric haulage systems, the suc-cessful installation of low cost shaft hoisting systems and improvements in conveyor design, alternative haulage systems are appearing as viable alternatives to diesel truck hauling. In particular, the aspects of ergonomic and environmental operating conditions, maintenance and operating costs as well as productivity rates are becoming more and more important in the selection of underground haulage systems. Future develop-ment of existing diesel haulage systems will require that diesel haulage units become more productive, have considerably reduced exhaust emissions compared to existing units and remain the cheapest haulage method for under-ground one way haul distances up to a distance of 3 kilometres. Development of electric truck and associated fuel cell haulage systems

Jan 1, 1985

IN presenting the following short paper the writer hopes to illustrate some uses of explosives in industrial work under conditions different to those prevailing on mining fields. This paper is based on experience gained at the Newcastle steel works of the Broken Hill Proprietary Company Limited. The management had decided that as soon as No. 2 blast furnace which is of an improved design was ready to be put into commission, No. 1 blast furpace was to be dismantled and reconstructed to a similar design to No. 2 furnace. This reconstruction entailed the removal of the brick lining of the furnace shaft, and, also the removal and disposal of the,"salamander" and hearth-lining. For the information of members who may possibly be unacquainted with the term "salamander," it might be explained that this term is used by iron metallurgists to denote the mass of iron and slag formed at the- bottom of the furnace, whilst in commission.The method of disposal depends upon the size and nature of the salamander, and in the case under review it was decided to bury it below the hearth of the 'furnace' to be reconstructed. A passage-way was made in the concrete walls of the cast house, and the sand-filling of the cast house removed sufficiently to allow of the concrete foundations of the furnace being reached. This passage-way was extended until the hearth was encountered. The next operation was the removal of the hearth-lining below the salamander. The removal of the concrete was not difficult...

Jan 1, 1921

Basicity(aO2−) has been known to affect the physicochemical properties of molten slags in the metallurgical processes. However, because of the impossibility of direct measurement of single-ion activity, various indirect measures such as capacity, redox equilibrium of transition metal ions, activity of basic oxides, and (theoretical) optical basicity have been proposed; but these basicity measures have been restricted within slag systems and the interaction between measuring elements and slag components has affected the quantitative estimation of slag basicity. Recently, since it was reported that solubility of noble metals in molten slags could be an indirect measure of basicity, the influence of slag basicity on the solubility of platinum and silver has been reported. The reaction mechanism of platinum dissolution into basic slags has been reported, whilst that in acidic slags has not (Nakamura and Sano, 1997; Sano and Nakamura, 1997; Nakamura et al, 1998). Richardson reported that the solubility of metals such as cupper, gold, silver, and lead in the CaO-SiO2-Al2O3 slag was presumably dependent on the atomic radius and the accommodation ability of the silicate network (Richardson, 1974). Swinbourne and You measured silver solubility in the Na2O-SiO2 slag over a wide range of oxygen partial pressure and suggested that silver would be present as both Ago and Ag0.5 in the slags (Swinbourne and You, 1999). For brevity, these previous works discussed the dissolution mechanism of silver into the slags based on the existence of silver as a neutral or molecular species. However, because the almost chemical reactions occurring in the slag are affected by the basicity, the reaction formula with O2- ion is required based on the ionic characteristics of the slag such as desulphurisation and dephosphorisation reactions as given in Equations 1 and 2, respectively.

Jan 1, 2000

For Australian mining projects, sustainable groundwater use is typically defined as a groundwater extraction regime, measured over a specified planning time frame, which allows acceptable levels of stress and protects dependent economic, social and environmental values (DEH, 2004). This principle is compatible with most stakeholdersÆ understanding of our national environmental objectives, yet the application of this policy on a project-specific scale is not always straightforward. Three examples of sustainability issues in the management of groundwater in mining are presented. These examples highlight each of the three dependent values: environmental, economic and social.

Jan 1, 2006