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The hazard posed by underground mine fires is illustrated in the first part of this paper by means of a review of experiences in four mining countries over the last three decades. This brief review indicates that while much progress has been made generally in preventing fires and providing means of protection to miners, the possibility of disasters occurring must continue to be regarded as very real. Based upon recent investigations by the South African mining industry, an integrated strategy for providing protection to personnel in the event of a fire is outlined in the second part of the paper. The main, complementary, elements in this strategy are the prevention of ignitions, the limitation of fires, provision of protection systems and equipment, training for emergencies, and effective implementation of safety measures. Some comments are made on important aspects of these elements and on possible further developments.

Jan 1, 1988

As a number of underground fires have unfortunately happened in the Broken Hill mining district, the writer trusts that a paper dealing with such a subject may prove of interest. To simplify matters, the subject is classed under three mainheadings- I Origin of fires; II Methods of subduing them; III Precautions to minimize the risk of their occurrence.Underground fires may be started in three ways - arson, spontaneous combustion, or carelessness.With regard to the first-mentioned cause, direct evidence is usually lacking to prove that any fire has been caused maliciously; Though definite proof of spontaneous combustion having been the cause of a mine fire has not been brought forward, nevertheless it should be considered, especially in the case of sulphide ore bodies of a more or less friable nature. The writer has been informed on reliable authority that in an open stope on the...

Jan 1, 1911

By Dunne R, Defilippi J

Dump leaching began at Teller in late-1988 at a rate of 4 MTPA and has been progressively expanded to the present rate of 10 MTPA. Teller's on-going commitment to dump leaching is driven by the amenability of gold ores to the process and the availability of large tonnages of low grade gold ore. The sequence of evaluating ores for dump leaching involves rolling bottle tests on coarsely ground ore, followed by small and large column leaching and finally trial heaps. Trial heap tests are very expensive and an alternative approach to this is large diameter column leaching.A four-column permanent facility was built at Teller to specifically evaluate the leaching characteristics of new dump leach ores. Details of construction, operation and dismantling are discussed in the paper. Capital cost for the four column facility was some $45 940, while operating costs are about $24 800 per column.

Jan 1, 1992

According to the temporal and spatial distribution of regional metallogenesis, the Pacific Rim can be divided into four global metallogenetic systems. The Asia-Australia W-Sn metallogenetic belt is the typical representative of intracontinen- tal metallogenetic systems. This belt resulted from Mesozoic and partly pre-Mesozoic tectonic magmatism, mainly re- lated to S-type granite of crustal source, that was generated by collisional orogeny combined with oceanic subduction in intracontinental and continental margin settings. Based on the concept of metallogenetic series, there is a group of min- eralised ore types showing a definite spatial and temporal distribution from endogenetic to exogenetic. These metalloge- netic series are widely distributed in the Asia-Australia W-Sn metallogenetic belt, and are well developed in Southeast China. Five metallogenetic series and two petro-minerogenesis evolution models have been established according to their tectonic settings, various types of granitoids and metallogenetic evolution.

Jan 1, 1995

At Yucca Mountain, USA, a tunnel is being built according to nuclear quality standards. It has proved possible to meet very high quality demands while at the same time achieving high advance rates. To be able to do this, routines on how to record and store quality related information have been established. This has meant that a new philosophy has entered the tunnelling industry. Especially for nuclear waste projects, of which Yucca Mountain is one of the first ones to be built, the experiences made and the quality assurance program established will be of great importance for future projects. The paper gives examples of what the Nuclear Quality Assurance system has meant in practice for the tunnelling at Yucca Mountain. And, it also explains why a non-grouted bolt, Super Swellex-, was chosen for long-term reinforcement in the tunnels which might host nuclear waste for thousands of years.

Jan 1, 1999

A substitute for rutile can be produced by leaching natural or pre-treated ilmenite in hydrochloric acid. Ilmenite in its natural form is an extraordinarily inactive mineral from which the selective removal of iron is rather difficult. The reactivity of ilmenite so that it can be leached with dilute hydro- chloric acid (=2O% w/w) can be enhanced by pre-treatment steps of oxidation and re- duction. The temperatures at which oxidation and reduction are carried out have an effect on both the kinetics of these steps and the leaching kinetics and optimum temperatures for oxidation and reduction are 950 and 850¦C respectively. The mechanism of leaching of iron from pretreated ilmenite and the effects of rate of agitation, temperature, acid con- centration and addition of ferrous chloride to hydrochloric acid on leaching kinetics and production of fines are discussed in the paper.

Jan 1, 1984

By Bangerter PJ

The use of gravity concentration is, and has always been, the conventional primary method for gold recovery from alluvial deposits. The development of high capacity cone concentrators and metallurgically efficient wash-waterless spiral separators has had some impact in the technology for alluvial gold processing, but perhaps more significantly has led to the relatively recent use of this gravity concentration technology in grinding circuits of hard rock ore for "coarse" gold removal and for scavenging gold locked in sulphides from cyanidation tailings streams.Gravity concentration systems are relatively low-cost, non-polluting and energy efficient; and their judicial use in gold treatment plants can significantly reduce overall capital and operating costs.The application of modern gravity concentration technology to hard-rock and alluvial gold ore treatment is discussed. Flowsheets and test and operating data from a number of gold processing operations incorporating gravity concentration treatment are presented.

Jan 1, 1984

The Lake Rotokaua sulphur deposit, near Taupo, New Zealand, is a lacustrine sedimentary ore body, 220 acres in area and from 7 ft to 96 ft thick, containing, within the area drilled to date, some 20 million long tons of ore averaging 25% elemental sulphur in unconsolidated tuffaceous diatomaceous clay, overlain by about 120 ft of pumice sand and by the shallow Lake Rotokaua. An additional amount of perhaps 4 million tons of sulphur is regarded as probable in the area remaining to be drilled. Current economic studies cover the problems of mining an unconsolidated water-saturated formation with some residual thermal activity nearby; conservation and restoration after mining in a scenic recreation area; beneficiation of the ore and extraction of high- purity sulphur, principally for fertilizer manufacture. The deposit has additional importance as a pointer to possible further discoveries in the Thermal Region.\

Jan 1, 1971

Interactive data exploration is essential for visualising grade distribution and geological controls on orbodies. Quick and appropriate computer techniques for making daily 'value adding' decisions include routine imaging of numerical data suc

Jan 1, 1998

Ore petrology will fundamentally determine the types of metallurgical processes employed for ore treatment, their operational efficiency and the nature of processing problems encountered. It is therefore paramount that the petrological charact

Jan 1, 1998

By W Whiten

The determination of mineral composition is necessary in the mineral sands industry. Tiwest has developed a procedure for safe and convenient determination of the mineral composition using a magnetic separation followed by chemical analysis using X-ray fluorescence spectroscopy. This then requires the conversion of the elemental assays to mineral compositions. A project at the Julius Kruttschnitt Mineral Research Centre has developed a convenient analysis method for this conversion. This analysis is based on a reconciliation of the of the assays of the sample with the standard mineral assays by making minimal adjustments based on the assay accuracies to both sets of assays. As well as providing the mineral composition it to be tested for other applications and variations of the procedure to be evaluated. Given a range of samples, testing for the accuracy of the assays of the standard minerals, has been demonstrated.

Jan 1, 2001

By A D. Farmer

Power ultrasound may be used in a number of ways to enhance the processing of minerals. It is both technically and commercially feasible to apply ultrasound to leaching processes in order to enhance the removal of contaminating minerals, or the rate and ultimate recovery of valuable mineral. When applied to the production of synthetic rutile from reduced ilmenite produced by the Becher process, its use proved beneficial to both the aeration and the final acid leach process. The enhanced performance is achieved through the very localised high energy release at the mineral surface from the collapse of cavitation bubbles produced by power ultrasound. This gives rise to two effects: initially, the rapid cleaning of mineral surfaces û of oxidation products and coatings of fine adhering gangue minerals û and the attenuation of the boundary layer at the mineral surface during leaching, which allows fresh leachant to contact the surface more readily.

Jan 1, 2000

While I contemplate the formidable catalogue of bodies and organisations participating in this Conference and the impressive array of qualifications chalked up after the names of the representatives I am indeed honoured to be invited to address you. When I consider the theme you have chosen for your conference I am also somewhat daunted: "The Twenty First Century - Mining for Mankind". It is indeed dramatic, challenging. But what, I ask myself, can a mere KCMG say to all you professional fellows and doctors and academicians? It is not for me to stray on to the more esoteric areas that you will be covering, thereby running the risk of teaching my grandmother how to suck manganese nodules. On the other hand it seems to me that you deserve more than the courtesies, not to say banalities, that are sometimes - sadly, and unjustly - regarded as the stock in trade of diplomats.

Jan 1, 1986

By Henley S

The year 2000 is not very far ahead - only five years. It should not be hard to forecast what will happen between now and then, because the technologies that will be in practical use then should all be at least in embryo existence now. There has been a historical trend for the mining industry to work ever more difficult and ever more marginal deposits. There are clearly a few exceptions and major discoveries, but the industry is becoming heavily dependent, at both the exploration and the mining stages, on technological innovation to retain acceptable profit margins. With the new exploration and mining technologies come requirements for additional computing support. Computing technology further allows the potential integration of a wide variety of different types of data to help the explorationist to build and test exploration strategies, or to help the miner to design and schedule mining operations.

Jan 1, 1995

By Concha F, Sampaio R

In most of the literature, the hydrocyclone is viewed as a black box in which only global variables are present and where the equations are obtained by curve fitting. Recently some work has appeared where the Navier Stokes equations are solved numerically in the hydrocyclone geometry. However, in all of these works the air core surface, which has an important influence on the hydrocyclone dynamical behaviour, is modelled as being a cylindrical surface of fixed radius. In this work, we model the surface of the air core as a free-boundary which has to satisfy a jump condition, the Young-Laplace equation, relating the physics to the geometry. Based on this model, we are able to explain, qualitatively, some phenomena that have puzzled research workers in the field for many years, and can show, through the air core behaviour, the influence of material parameters on the performance of the hydrocyclone.

Jan 1, 1993

By Aust M. I E

IT is the custom, I must admit, for a presidential address to be a review of the progress during the year of the institution presided over, and of the sciences and arts within its ambit. On this occasion precedent is departed from in favour of a subject by request.As man has at last, in employing gravimetric and electrometric methods of subsurface research, started on the rational use of divining rods with some knOWledge of their governing laws and principles, and with some ability to interpret the results obtainedfrom them, I was asked to add to the voluminous literature of the quack or empiric divining rod. James Mansergh, the author of Melbourne's sewerage system, in his presidential address before the Institution of Civil Engineers in 1901, admitted he was afraid touse the hazel rod lest in sinking on its indications to some solution.

Jan 1, 1928

This paper sets out a number of means by which professionals can reduce or eliminate the risk of professional liability whether as directors, employees, partners, independent consultants or contractors. A relationship between client and professional is commonly cited as an example of a fiduciary relationship: the professional "undertakes or agrees to act for or on behalf of or in the interests of' the client "in the exercise of a power or discretion which will affect the interests of that other person in a legal or practical sense."2 As a fiduciary, a professional must ensure that his or her exercise of power does not result in a position of ascendancy or undue influence over the client. Also, a professional must avoid situations where there is scope for even the perception of potential conflict between his or her professional duty to the client and his or her own Interest.

Jan 1, 1995

Coal water mixture (CWM) is a mix of finely ground coal with water and a small amount of chemicals. It is a new way of transporting and handling coal. CWM can be transported, stored and burned like fuel oil in steam generating boilers. It also has some environmental advantages over both oil and bulk coal. A group comprising Ube Industries Limited, Nissho Iwai Corporation (both from Japan) and Coal & Allied Industries Limited has been working in Japan and Australia since 1987 on a joint feasibility study into the production, transport and marketing of CWM from Australia to Japan. The group has been studying the development of a large-scale CWM plant on Kooragang Island at the mouth of the Hunter River at Newcastle, NSW. The project concepts and engineering plans for the CWM plant are well advanced and other studies related to the project are continuing.

Jan 1, 1995

A typical large surface mine in Scandinavia has hard rock, a cold cli- mate, poor ore, a complicated vein type orebody and high labour costs. In order to survive, these mines have to maximise their ore production, minimise waste extraction and get the most out of every man hour. This article describes two examples of how inclined blastholes drilled with hydraulic percussive drills can help to meet these requirements. Both of these Scandinavian mines, Kemira Ltd's Siilinjarvi mine in Finland and Sydvaranger A/S's Bjornevattn iron mine in Norway, use inclined blastholes of 200 mm in diameter. The Siilinjarvi quarry is using inclined holes in production drilling. The Bjornevattn iron mine is blasting the final pit walls with inclined holes. The benefits gained when using inclined instead of vertical blastholes are better selectivity, better bench drilling conditions, steeper final pit walls and increased safety.

Jan 1, 1989

By Strickland R. E J

Heap leaching is establishing itself as an efficient method for the extraction of gold from low grade ore. It has the advantage of low capital costs, low operating costs and rapid startup. However, not all ores are amenable to heap leaching. It is only applicable to well oxidized ores that have reasonable permeability characteristics. Ore with excess fines or clay often display low permeability and are unsuitable for heap leaching.In this study, an attempt has been made to increase the rate of cyanide leach solution percolation by flocculating clay particles or reducing the surface tension of the leach solution. A wetting agent was found to decrease the rate of gold dissolution, possibly by presenting a hydrophobic surface to the gold particle. Flocculation of the clay increased the solution flow rate. The flocculation agent had no affect on the total gold leached but decreased the leaching rate.

Jan 1, 1992