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An international raw material partnership, a $164 million 900,000 long ton per year aluxAna plant; an ideal location at Gladstone, Queensland, Australia - this is Queensland Alumina Limited, on stream in 1967 expanded 50 per cent by the end of 1968. Queensland Alumina Limited is the world¦s most modern alumina refining operation which is owned by an international consortium of four companies; Kaiser Aluminum & Chemical Corporation of the United States with 52 per cent; Alcan Aluminium of Canada with 20 per cent; Pechiney of France with 20 per cent; Conzinc Rio Tinto of Australia, 8 per cent. Q.A.L. operates as a co-operative -- the partners do not draw profits from the venture. Instead, each member of the consortium draws alumina in proportion to his share of the ownership. The method of disposal of this alumina is for the partner to decide.

Jan 1, 1969

By E du Plessis, J Kapusta, J L. Mauk

The world-class Bulyanhulu gold deposit (375 t Au) is in the Sukumaland greenstone belt, Northwestern Tanzania. The main mineralised quartz vein structure, termed Reef one, occurs at the contact of felsic metavolcanic rocks on the hanging wall and mafic metavolcanic rocks on the footwall. Reef one is dominated by massive quartz together with pyrite, pyrrhotite and minor chalcopyrite. Alteration in the footwall basalt is characterised by extensive chloritisation, calcification and silicification, which is strongest near the vein. Sericitisation also locally occurs adjacent to the vein. Metamorphic hornblende and plagioclase (albite) increase in abundance at a distance of 120 m from the vein and reflect the gradation into less altered rocks. The increasing abundance of chlorite, calcite, quartz and local sericite near Reef one, coupled by replacement textures suggests that most of these footwall minerals are the product of hydrothermal alteration, rather than regional metamorphism. Geochemical data shows slight enrichment in Ca, Fe and As towards the vein, whereas Zn in several drill holes becomes enriched away from Reef one. The Bulyanhulu gold deposit is a quartz-pyrite-chalcopyrite shear controlled vein with an adjacent extensive chlorite-quartz-calcite hydrothermal alteration zone (and a limited local sericite alteration zone) that passes to a hornblende-albite metamorphic assemblage further into the footwall.

Jan 1, 2002

By Manzoori AR

From a detailed combustion testing program and earlier experience with Leigh Creek coal, the Electricity Trust of South Australia (ETSA) gained a wide insight into the use of low rank coal fired boiler plant. This work is fundamental for the selection of boiler design parameters and other details which in turn determine the correct coal deposit selection for future power station development. In addition it gives boiler designers a good indication of the measures required to give reliable plant operation. Extrapolation from experience with existing plant, the designers main source of information, was not considered appropriate because of the lack of experience with similar coals. Brown coal beneficiation is also being assessed by ETSA in an attempt to improve the coal quality by the pretreatment of the raw coal prior to combustion in future coal.fired boilers. ETSA is also involved in the development of circulating fluid bed and gasification processes to determine whether these alternative processes are a more viable method of utilising the South Australian coals than pulverised fuel firing.

Jan 1, 1987

A very sensitive high-speed two-colour pyrometer was built to measure the temperature of single particles of sulphide mineral, typi- cally 50 pm in diameter, as they burnt while entrained in a hot gas stream. The pyrometer has been used to study the burning of pyrite and chalcopyrite particles and has thrown light on cenosphere formation. Measured maxi- mum temperatures have been compared with values predicted by diffusion-based models. The pyrometer has also been used to study the burning of small captive pellets (2-9 mmm dia- meter) of lead-zinc concentrate.

Jan 1, 1984

By G C. Kiel, G J. Nicholson

Corporate governance has never been more topical. A glance at any major newspaper or business publication will reveal a litany of corporate failures based upon the governance of the organisations involved (eg Byrne, 2002; Hayes, 2002; The Economist, 2002). The increased compliance requirements and speculative nature of our industry means that corporate governance systems are, if anything, more important than in the general business community (Arthur, 2001). Rather than focus exclusively on the contribution of governance to corporate failure within the mining industry, however, our objective in this paper is to examine how boards can add value to the corporations that they govern. In order to highlight how a board can add value to a company, we commence by outlining the role of the board in the modern corporation in general and the mining industry in particular. We then introduce the concept of shareholder value and identify the steps on which a board needs to focus to enhance shareholder value through value tracking processes. Our discussion pays particular attention to the importance of organisational culture to the companyÆs activities and utilises three case studies from the mining industry. We conclude with an overview of what mining boards can do to enhance their culture and drive performance changes for the benefit of the companies they govern.

Jan 1, 2002

The seminar had its origins in an Inquiry into the Box Flat Disaster and one of the conclusions from this Inquiry was that there should be a better dissemination of technical knowledge and the results of research work. As a result of this Mr. W. Roach, Chief Inspector of Coal Mines in Queensland and Mr. R. Menzies, Chief Inspector of Coal Mines in N.S.W. had a meeting to see how this could be done. They concluded that it would be difficult to have the sort of regular meetings that would be possible where distance was not significant, but a seminar would be a major step toward satisfying this particular conclusion of this Inquiry. As a consequence, Mr. Roach, who is on the Committee of the Southern Queensland Branch of the Institute, suggested when the Branch programme was being planned this year that a meeting of this type should be held, and the Mine Fires Seminar which was held today is the result. We have received a great deal of support in arranging the Seminar. First and foremost I wish to acknowledge support from the National Coal Board in United Kingdom. Not only have they released Dr. Willett for a period of six to seven weeks to visit Australia, conduct the Seminar and give a series of lectures in various areas through the country, they have also borne the brunt of the financial support that has been necessary to make this possible. In addition we have received considerable support from many organisations in Australia. I 'mentioned this

Jan 1, 1973

The BLEG (Bulk Leach Extractable Gold) technique is a semiquantitative measure of cyanide extractable gold contained in a sample. A 5kg sample is leached in cyanide solution for 24 hours and gold is precipitated out of the pregnant solution using zinc and assayed by AAS. The detection limit is reported as ppb (parts per billion). Telfer is located 1300km north north-east from Perth in the Great Sandy Desert. The climate is one of hot summers with irregular rainfall and mild winters. A large portion of the area is covered by aeolian sand and seif dunes with poorly developed drainage, rare outcrop; topographic relief is a maximum of 96m. Poor outcrop and poorly developed drainage render conventional stream sediment sampling and soil geochemistry inadequate. Therefore a technique providing a minimum number of samples with maximum accuracy and sensitivity was needed. Consequently BLEG orientation surveys were conducted over the Telfer Mine area in 1983, 1984 and 1985.

Jan 1, 1988

By O Ostrovski

Direct iron smelting reduction has been examined using a modified 50 kg induction furnace. The furnace was equipped with continuous raw material feeding, a top oxygen lance, argon bottom bubbling, and sensors for measurement of gas and bath temperatures, gas composition and other parameters. In the base case, iron ore was charged at the rate of 1.5 kg/h, coke flowrate was adjusted to maintain a char fraction in the slag at 30 wt per cent, the oxygen flowrate was 100 Nl/min and the post-combustion ratio (PCR) was 60 per cent. The PCR was varied from 45 to 75 per cent by changing the lance height relative to the bath surface. Smelting reduction of Whaleback iron ore was investigated at different post-combustion ratios and iron ore feedrates using coke and coals with different volatile matter. The rate of iron oxide reduction increased with increasing iron oxide concentration in the slag, with a slight deviation from a linear function. The post-combustion ratio affected iron ore reduction and partitioning of elements between phases in the smelting reduction furnace. The high volatile coal investigated was found to be unsuitable for iron smelting reduction in the laboratory furnace.

Jan 1, 2000

This paper discusses basic practices of operation applied to raise drilling. It draws attention to critical areas that tend to be neglected. A brief history covers development of raise drills. The elements of the equipment, derrick assembly, drill string and reamers are ex- amined. Particular emphasis is on the drill string. It is concluded that manufacturer and operator can benefit each other by closer interchange of ideas.

Jan 1, 1977

The introduction of legal certification of mine managers is a matter of history. It was introduced as part of legislation for mine safety. It has been said that such legislat- ion was written in blood. Like all legislation this legislation is divided into three sections; commands, obligations and sanctions. While legislation in all States on this subject is similar, the differences are great enough to have prompted the preparation of a Uniform Code by the Annual Conference of Chief Inspectors of Mines. This Uniform Code has not been adopted fully by any State to date. Legal certification of mine managers has made managers more aware of the requirements of the legislation covering their industry, legislation that reads as a summary on past accidents and methods of preventing them. While budding managers spend considerable' time in their early years in the preparation for certification, history has shown that the industry has benefited from their efforts. A better knowledge of the safety acts by the managers has produced safer operations, and a higher standard of management has raised the technical standards of mining operations to a stage where Australia can be proud.

Jan 1, 1980

This paper explains why the valuation of mining assets is often a very different exercise from the valuation of the shares in the mining company which owns those assets. The fundamental reason for this is that mining assets, and the shares of the company which owns those assets have different risks. In order to properly value mining securities it is essential to: ò ensure all the different risks and other factors which impact on the value of the mining assets and the value of the shares are taken into account; and determine the extent to which the different risks and other factors are addressed in the value of the mining assets and the value of the shares so as to avoid double counting or not counting at all. If the alternative, but far from consensus, view is accepted that the correct valuation methodology to apply to shares in mining companies should be based on option pricing theory then conventional valuation practice of both mining assets and shares in mining companies will need to be fundamentally reassessed.

Jan 1, 1994

In any strip coal mining operation the aosL important single operating unit is the dragline. Because the capital and operating costs of a dragline are high, it is desirable to operate these machines at their maximum efficiency. Thiess Bros. Pty. Limited operate a Bucyrus-Erie 1350 Walking dragline at their Callide coal mine. The operating conditions at the Callide Mine are different from those of other coal mines situated in Central Queens ,nd. The topography is rugged, the coal seam is thick, and the overburden is hard and inter- HH,inded. Several different operating techniques for a large dragline working under these con- ditinns arc discrossmd it tt

Jan 1, 1978

A simple and rapid method for delennining gold and silver in carbon samples is described. The method involves dissolution of carbon ash in a strong oxidising medium of aqua regia and hydrofluoric acid. Gold and silver are determined in the resultant solution using atomic absorption speetrometry (AAS). The method is efficient and reproducible. Gold results are comparable to the standard fire assay results, with agreement of results within ± 5 per cent. The co-efficients of variation for gold and silver are 0.37 and 0.39 per cent respectively for six replicate analyses. The analysis of gold and silver in a batch of ten carbon samples can be completed in approximately four hours.

Jan 1, 1992

Mount Isa Mines Limited commissioned the Heavy Medium Plant in August 1982. The first processing stage using Mogensen Sizer 2056 dry screens, experienced unresolvable cloth blinding problems in attempting to separate fine, damp Lead/Zinc ore at 1.7 mm. A large proportion of the fines incorrectly reported to oversize and hence to the wet preparation screens. This wet preparation screen overloading produced multiple operating and maintenance problems. The plant configuration precluded retrofitting any alternative proprietary screen. An internal Mount Isa Mines research and development programme was established to design and build a screen to achieve the required per- formance within the site constraints. The resulting ISA SIZER screen has exceeded metallurgical performance expectations. A `clean sheet' approach to the design also permitted elimination of maintenance difficulties experienced with the Mogensen Sizer. Four `production model' ISA SIZERS were installed in February 1988. The ISA SIZER screen, now fully developed is available commercially and will satisfy many screening plant requirements.

Jan 1, 1988

In recent years a number of explosive blends including ANFO, emulsion and watergel products have been used in a variety of ground types and applications. These `standard' explosives' technologies are not new, but out of the uses and applications, have sprung a new generation of tailored explosives that match the ground type and the operating environment. This is in stark contrast to the norm, where various patterns and loading configurations have traditionally been designed to accommodate the explosive. This paper discusses these tailored explosives and the explosives' technology behind why they work. Active tailoring of explosive formulations can save mining dollars while essentially leaving the explosive price unchanged. Tailoring explosives may lead to increased rock breakage, heave, digging rates; lower digging maintenance costs and in some cases replacing earth moving machinery altogether. Tailored explosives may have other benefits such as reduced over pressure compared with standard alternatives. The tailoring of explosive performance generally involves three major methods (other than changing the bulk density and sensitivity): (i) replacing fast burning reactants with slower burning reactants or vice versa; or (ii) leaving the explosive intact and diluting the entire explosive with slow burning or `inert' material; or (iii) changing the concentration of the fuel/oxidiser mix. When tailoring explosives for particular applications, authorising, testing, costing, manufacturing, and delivery systems must also be taken into account.

Jan 1, 1995

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

The Illawarra Branch of the Australasian Institute of Mining and Metallurgy over recent years has established an enviable reputation for organising and conducting conferences, colloquia and symposia. And this Symposium must surely enhance that reputation. The subject of the Symposium, Seam Gas Drainage has become a matter of great import- ance to the Australian Coal Industry in a comparatively short time. Our short experience being due to our operations, until recent times anyway, not being unduly affected by gas. The Australian Industry, by virtue of its mines getting deeper and higher rates of extraction being required is now encountering the difficulties with gas which have for so long been part of the coal mining scene in many other countries. Because these gas emissions affect our working conditions by way of creating hazards and affect our production by way of bringing about cessation of operations from time to time this Symposium must be regarded as being very timely out here. I must congratulate the Branch Committee on the general set,yp :o.f the programme of papers. The classification of papers into four groups and the sequence in which the papers were presented provided an excellent flow through from introduction to finality. It is not my intention to further discuss individual papers - already they have been well discussed in this forum and as I understand it outside in the early hours of the morning,

Jan 1, 1982

The Lower Palaeozoic Woolomin Association is composed of chert and jasper (often radiolarian), siliceous argillite, the mafic volcanics with associated hyaloclastites, and occasional greywacke and limestone lenses. Several "Cyprus-type", conformable pyritic copper (+/- zinc and cobalt} sulphide lenses are spatially related to individual mafic volcanic units and manganiferous chert and/or jasper. The Association has been interpreted to represent an oceanic crustal remnant generated either in an island arc environment (Herbert, 1981) or at a divergent plate boundary (Scheibner and Glen, 1972; Leitch, 1974a, 1975) later to be obducted, or tectonically emplaced, into continental crust; the adjacent Peel Fault was considered to be the palaeo-obduction zone (Scheibner and Glen, 1972) and the associated alpine-type mafic/ultramafic complex, an ophiolite (Crook and Felton,1975).

Jan 1, 1990

By Lysnar R, Horswill M

Since the introduction of the pocket calculator, electronic measuring equipment, lasers and computers, the mine surveyor's approach to his work has changed. Where he once used steel bands he now uses infra-red, visible light or radio waves. The reading and storing of angles is done automatically and he now has to be familiar with the facilities that a computer can offer, instead of plotting and calculating manually. This highly sophisticated equipment is continually being upgraded, modified and fine tuned. This paper will attempt to highlight some of the equipment at present in use by the surveying profession and research currently being conducted by the WA School of Mines. The various options in EDM will be considered including the latest unit capable of measuring distance without the benefit of a reflector, thus enabling the surveyor to co-ordinate points that were previously thought inaccessible. The School is currently working on changes to the GAK1 Gyro Theodolite which may improve results and enable the operator to have more control and confidence in his observations. Areas under consideration are improved lighting, binocular viewing and interfacing the instrument to a stopwatch. In the last few years the computer is being used not only for surface pickups and control but also for underground work. We will highlight the underground options in this area and the software available.

Jan 1, 1987

The relevance of borehole and bore core evaluation to the design of underground coal mines is illustrated by considering the technical parameters of colliery design and the information from which they are constructed. The nature of this information is described, together with some methods for its storage, processing and presentation. Geophysical exploration techniques are compared as information sources. It is concluded that borehole and bore core evaluation is relevant and necessary for colliery design, but that optimum results will be obtained if drilling can be combined with geophysical techniques. Because of the inherent uncertainties in prediction of mining conditions the necessity of obtaining as much information as practicable from drilling evaluation is also stressed.

Jan 1, 1977