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By Belcher C. B

The Groote Eylandt manganese ore deposits contain mainly pyrolusite and cryptomelane with lesser amounts of the manganese minerals lithiophorite, todorokite, psilomelane, and nsutite. The major non-manganese minerals which occur are quartz, kaolinite, and goethite.Determination of the mineralogy relies mainly on x-ray diffraction analysis. Quantitative methods for the determination of pymlusite and cryptomelane in Groote Eylandt manganese ores have been developed, A large amount of isomorphous substitution may occur in the manganese minerals and a number of minor and trace element associations have been noted. A correlation has been established between the potassium and cryptomelane contents for a wide range of ore types. Anomalous calcium, magnesium, and sodium values occur in samples containing todorokite, and barium is associated with psilomelane. Groote Eylandt lithiophorite appears to contain negligible amounts of lithium (<O· 05 per cent).A relationship between the H20+ and the Al203, K20, and Fe203 contents has been estahlished indicating that much of the combined water content is due to the presence of kaolinite and goethite, and cap be removed by beneficiation of the ore.

Jan 1, 1975

Stripping of Fe (III) from D2EHPA Using Different Reagents The common way to extract Fe(III) from an organic solvent is by using concentrated acidic solutions. The stripping of Fe(III) from organic solvent Di-2-ethylhexyl phosphoric acid (D2EHPA) by hydrochloric acid (HCl) solutions has been found to increase with increasing the acid concentration. However, the use of a concentrated acidic solution such as 6 M HCl can degrade the organic molecules. In this research, to increase the efficiency of Fe(III) stripping from D2EHPA, effect of some acids, salts and buffer solutions was studied. Influence of Tri-butyl phosphate (TBP) as modifier on the Fe(III) stripping operation was also investigated. According to the results, the best Fe stripping recovery was achieved in the presence of low acid concentration and the salts which was 72.4 per cent oxalic acid, 70 per cent ammonium oxalate and 75 per cent buffer of oxalic acid and ammonium oxalate. The results also showed a better recovery in the presence of the buffer rather than the salt. Finally, increasing the concentration of TBP, HCl and H2SO4 resulted in a higher stripping efficiency of Fe(III). However, in the presence of oxalic acid and its salts increasing the reagent concentration did not increase the stripping efficiency and at this condition, the recovery of iron remained constant.

Sep 13, 2010

Studies of the Main Seam in the Rapahoe Sector of Greymouth Coalfield have shown that the proportions of palynomorphs and palynomorph groups vary vertically within the seam, but remain laterally consistent. Subsequent examinations of other seams in the Rapahoe Sector have demonstrated that the changes in palynomorph proportions observed in the Main Seam are specific to that seam, effectively providing a seam 'fingerprint'. Such a characteristic signature may be used to identify the Main Seam where faulting or seam splitting confuses seam correlation between drillhole intersections. Palynomorph assemblages are derived from the original plants which formed the peat mire, and yield information on mire conditions such as climate, mineral matter input and chemistry. These depositional factors influence coal properties such as mineral content, volatile matter yields and coal breakability. Palynological data can therefore assist in development of depositional lTIodels for prediction of coal quality variations. Several other, thiner seams in the Rapahoe Sector have been demonstrated to also contain recognisable palynomorph assemblages, suggesting that other seams may also possess distinct palynomorph abundance profiles.

Jan 1, 1996

By S L. Garwin

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Since the Eocene, New Guinea tectonics have been driven largely by the south-westerly-directed collision of accreted arc terranes with the northern margin of the Australian Craton, and subsequent westerly-directed transport of these exotic terranes by left-lateral strike-slip fault systems. The subduction of the Solomon Sea plate beneath north-eastern New Guinea in the mid- to late-Miocene led to magmatism and related gold-copper porphyry and epithermal mineralisation in the Maramuni arc and the formation of the Frieda River, Nena, Wafi-Golpu and other deposits.The development of the world-class porphyry and epithermal deposits in the Medial New Guinea magmatic belt, including Grasberg, Ok Tedi and Porgera, is localised by dilational zones formed about the intersections of north-easterly-trending, reactivated basement faults and north-dipping reverse faults related to the southward progression of the Papuan fold belt during the Late Miocene to Pleistocene. These deposits probably formed during short mantle-derived magmatic episodes in zones of regional isostatic uplift, which are attributed to the delamination of the lithospheric mantle beneath New Guinea.CITATION:Garwin, S L, 2015. The tectonics, geology and gold-copper metallogeny of New Guinea, in Proceedings PACRIM 2015 Congress, pp 151–164 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

EARLY in 1911 the Public Service Board of New South Wales suggested the advisability of inaugurating a School of Mines at Broken Hill, arid made inquiries to determine how such an institution should be conducted. He, the author, believed the Board, as a result of the inquiries, was in favour of the project being worked in conjunction with the Technical College, and hoped to be ready to receive students at the commencement of 1912. That the inauguration has not yet taken place is probably due to the vast amount of consideration and preparation that a new departure of the sort would require. At the present time New South Wales or, to speak more broadly under the same denunciation, Australia is not at all suitably catering for the technical training of young men to provide the increasing demand for officers to work the valuable mines within its territory...

Jan 1, 1912

This paper is a collection of thoughts and frameworks. It addresses a simple question: æIf we are to believe the large number of people and institutions indicating that humans are destroying the Earth and that the end is nigh, why do we bother trying to be sustainable?Æ The paper lays out evidence for the existence of multiple hazards to global society. The existence of a hazard alone is insufficient to make an assessment of risk. Risk estimates are required to support decision-making. An approach to assessing risk is provided and some limited data are presented. A new ædefinitionÆ or statement of what sustainability (in a broad sense) might have become is then given. A decision framework for guiding decision- making about the risks is developed. This framework includes a definition of leadership with inherent implications for what determines whether a leadership position by title is actually leading. The paper concludes by offering a view of minerals industry sustainability and considerations around maturity in the current economic situation. It is hoped that by placing this collection of frameworks around sustainability, a supporting structure emerges that will facilitate action. It is proposed that action taken in this way will be more effective than reaction to regulation or even social license to operate imperatives because it is driven by a more holistic view of the challenges and the potential roles of individuals û all of whom are potential leaders at some scale of action.

Jan 1, 2009

By L Hussey, H Thanasekaran, J Kohmuench

Conventional flotation technology has historically failed to achieve high recoveries when treating <15 µm particles (Lynch et al, 1981). The new StackCell™ flotation technology was developed to specifically target this particle size range, and was tested at pilot plant scale at Mt Keith Nickel Concentrator. The streams tested, Slimes Rougher Tailings and Fines/Slimes Cleaner Tailings, represent 21% and 11% of the total nickel lost to tailings in the plant. Laboratory scale test work indicated that an economically significant fraction of these losses was consistently available to be recovered by additional flotation. The pilot plant experimental scope included over 50 tests. A grade recovery curve for each stream was developed, as well as information on the effect of ore type, feed rate, wash water, air flow, collector and frother on the performance of the cell. The single StackCell was able to achieve nickel recoveries of 16.8% and 16.5% on the Rougher Tailings and Cleaner Tailings, respectively, at grades consistent with these blocks. Additional test work of the StackCell in a cleaner scalper duty yielded final quality concentrate with a maximum nickel recovery of 59.5% for the single stage StackCell. Laboratory scale simulation of the downstream impacts of the StackCell operating as a cleaner scalper indicated a net recovery benefit of up to 2.0% for this cleaner block.Tests were completed to compare residence time requirements of the StackCell, as compared to conventional flotation. In 55 seconds, the pilot plant StackCell achieved 50% of the recovery of a 960 second laboratory scale conventional flotation on the same feed material. The apparent improvement in flotation kinetics is attributed to the novel high intensity aeration system, which provides efficient bubble-particle contact thereby shortening the residence time required to achieve high recoveries. The smaller footprint and lower energy costs of such a cell are also benefits of this technology, which is being considered for industrial scale installation as a result of this test work. Given the industry’s historical poor performance treating slimes with conventional flotation, it is clearly best practice to challenge the status quo through innovative new technology, such as the StackCell.CITATION:Hussey, L, Thanasekaran, H and Kohmuench, J, 2017. The application of high intensity flotation technology at Mt Keith nickel concentrator, in Proceedings MetPlant 2017, pp 259–278 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

By McKenzie A. M

The Corridor ore body is so named because it occurs in an east-west zone or corridor of schist bounded on the north by the siliceous conglomerates of Mount Lyell, and on the south by similar conglomerates of the Tharsis ridge (Fig. 1). It was discovered after the geophysical prospecting methods described below had defined a target zone for diamond drilling.Since the proving of copper mineralisation by drilling, the corridor orebody has served the vital function of a convenient known target body for the orientation of more recently developed geophysical methods. Traversing of the orebody by these new methods has provided experience for the evaluation of anomalies elsewhere.Some of the methods applied had not been used in Australia before, and were introduced to the west coast of Tasmania through the undertaking there of modern regional exploration programmes. The authors feel that the information gained could be of assistance to others engaged in geophysical prospecting.HISTORY OF DISCOVERYProspecting in the Mount Lyell district has been more or less continuous since 1881. The first geological report was published by Thureau (1886).In 1934, Blazey and Douglas (1934-38) commenced geophysical surveys at Mt. Lyell using the equipotential method.They obtained anomalous indications in several discrete zones and actually detected the south-east half of the corridor orebody but their work never became the basis for...

Jan 1, 1961

By E J. Hofmann, J E. Hofmann, A J. Hofmann-Fritz

"With its Head Quarters in Perth, global heavy engineering company Hofmann Engineering is one of the largest family owned engineering companies in Australia. The company has pioneered a number of new manufacturing processes and design improvements for components of large comminution equipment.Some of these innovations are: Innovative design improvements of high pressure grinding roll (HPGR) forged steel tyres. Hofmann Engineering has developed unique patented tungsten carbide stud and edge protection designs which improve wear life and introduce quick and cost effective replacement options to further extend the life of the tyre. Development of forged fabricated mill heads using rolled and welded high tensile steel plate as an alternative to cast conical mill heads. Establishment of Australian capability to manufacture and export up to 42 ft. (12.8 m) diameter SAG mill shells. Techniques for fast track, product improved replacements of cracked or damaged mill gears, including in situ profile & wear measurements of girth gears using portable coordinate measuring machine (CMM) technology, forged rim steel and induction hardening technology. Gear and pinion mechanical drive designs to 24 MW or higher for SAG mills of 38 ft. to 42 ft. (11.6 m - 12.8 m) diameter as reliable alternatives to gearless drives.The paper presents case studies from the Australian heavy manufacturing facilities of Hofmann Engineering on large, high powered equipment for both the domestic and export markets.CITATION:Hofmann, E J, Hofmann, J E and Hofmann-Fritz, A J, 2013. Australian innovations in high pressure grinding rolls and large grinding mill manufacture, in Proceedings MetPlant 2013, pp 141-151 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013

A rotating disc geometry was used to provide a uniformly accessible surface for a kinetic study of the cementation of cadmium, lead, and silver from dilute aqueous solutions. This work is an extension of studies carried out on the Cu-Zn and Cu-Fe systems for which the reaction rate was found to be completely solution phase mass transfer controlled.When the amount of material deposited was greater than 0·2 to 0·4 mg/cm2 there was an apparent enhancement in rate which is attributed to the formation of a roughened deposit. This same phenomenon was observed in the Cu-Zn and Cu-Fe systems. Again, the rate of reaction of each system investigated was found to be solution-phase mass transfer controlled.

Jan 1, 1971

By Whang K, Choi H

A study of flocculation of ultra-fine coal particles by ultrasonic waves was investigated on a laboratory scale.The coal suspension was dilute, with low ionic strength, and at pH 6·2.When a stationary sonic wave is set up in a solution containing suspended coal particles, it is believed that high and low pressure regions are alternately established at the half wave-length of the sonic wave and this resultsin the migration of coal particles towards the low pressure regions.As expected the flocculation is more effective as to frequency and the power of the ultrasonic waves is increased.The shape and size of the test equipment are also important variables.

Jan 1, 1977

By P Rubie, B Morgan, J Russell, C Stewart

The relationship between efficient liner exchange, concentrator availability and concentrator profitability is well documented. Russell Mineral Equipment’s (RME) relationship with OZ Minerals’ Prominent Hill site personnel enabled sound collaboration between the two parties. Both parties worked together to identify the sources of productivity and efficiency loss and developed solutions to reverse them.This paper chronicles the identification of production inefficiencies and the resulting removal of mill relining from the critical path through the materialisation of mill relining optimisation strategies. Furthermore, this paper outlines other recent mill relining optimisation strategies developed by RME and tested at Prominent Hill, to demonstrate and achieve further productivity, efficiency and safety improvements.CITATION:Rubie, P, Russell, J, Morgan, B and Stewart, C, 2017. Mill relining optimisation – a story of collaboration, in Proceedings MetPlant 2017, pp 335–345 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 11, 2017

The stability of parallel underground coal mine galleries and pillars have been investigated using two- and three-dimensional (3D) numerical stress analysis. Anisotropic horizontal in situ stresses and the direction of the excavations have been considered in the numerical analysis. The stability of the tunnels driven in a coal seam at various working depths has been investigated taking into account different strata conditions and then results from two- and three-dimensional numerical modelling studies were compared. Maximum principal stress components have been chosen in three various directions: vertical, parallel and perpendicular to the tunnel axis. Analysis have shown that in the anisotropic in situ stress field, the favourable direction of underground mine openings which have different strata conditions depend not only on the horizontal in situ stresses but also on the vertical in situ stresses. Furthermore, 3D numerical modelling studies have been carried out to investigate stability of multiple entry longwall panel gate roads and pillars with various width-to-length ratios (W/L). Results of the modelling studies have shown that the critical dimension of coal pillars depends on their width and the direction of maximum horizontal stresses.

Dec 6, 2010

By Milner A, Brockway D, Hodges S

The combustion of brown coals in Latrobe Valley power stations produces approximately 500 000 tonnes of solid wastes each year. This material, which includes precipitator ash, char and furnace ash, is hydraulically sluiced to large ashing ponds and the supernatant solution is ultimately discharged to the sea. There are significant operational and capital costs associated with the current ashing system. The ash produced from the Latrobe Valley coals is unique and has a wide variety of potential applications including soil conditioning, concrete and cement extenders, fillers in non-metallic materials, components of building products. In addition, with the application of appropriate technology, it is possible to extract char, sodium sulphate, calcium carbonate and magnesium metal (as the chloride) in substantial quantities from the ash. Research has been carried out to explore the prospects of these various options for ash utilisation. The research has focused on detailed characterisation of the ash material and the potential extraction efficiency for various species under various conditions. From this work a conceptual process has been developed and subsequent studies have been directed towards understanding variables and optimising operating regimes for product extraction. Currently, the work is concentrating on the separation of char, the development of high-grade carbon products and the extraction of sodium sulphate.

Jan 1, 1992

THE Great Cobar Company Limited owns 1100 acres of freehold, which include the Great Cobar Oopper Mine and smelters, the Cobar Gold Mine, the Cobar-Ohesney Copper Mine, and the Great Peak Gold Mines.ORE OCCURRENCEThe ore-bodies in the first three mines-namely, Great Cobar Copper Mine, Cobar Gold Mine, and Cobar-Ohesney Oopper Mine are, speaking generally, lenticular deposits of evidently more or less complete metasomatic replacements of the country rock along a line of powerful faulting. These lenses vary from 150 ft. to 400 ft. in length, and from 20 ft. to 100 ft. in width.

Jan 1, 1919

By Ray H. S, Galgali R. K

It is well accepted that the blast furnace will continue as the main route for iron-making for many more years. However, its limitations have motivated researchers to look for alternative routes, particularly, those where non-coking coal is used for liquid iron production. Smelting reduction (SR), where coal and oxygen are used to produce liquid iron and power is now receiving serious attention. Several smelting reduction reactors are now operating in pilot plant scale and one or two have reached commercial status.

Jan 1, 1999

Professor Skeats said: I wish at the ,outset to express my appreciation of the h0!-l0ur conferred on me by my election as President of this Institute for the ensuing year. The selection of a geologist for this position by a body of mining engineers andmetallurgists may be taken as an indication of the recognition that the subject is one which may play a useful part in the great metal industry. Among the records of primitive man the finding of implements of bronze and of iron indicated one of the important, advances made in human civilization, and shows that...

Jan 1, 1924

In referring to two subjects of interest to the Members of this Australasian Institute of Mining Engineers, I would at the outset desire to express our gratification that to-day we are able to welcome as now united with ourselves, those members who until recently constituted the New Zealand Institute. It is hoped that the amalgamation so amicably arranged may be productive of the best results to all concerned, incorporated as this combination has been at the moment of the fulfilment of that greater political union, the Australian Commonwealth.Since last Annual Meeting held in Brisbane, we have come under the same roof as the Chamber of Mines of Victoria, and we entertain the hope that as that Chamber and this Institute possess so many interests in common in the encouragement and advancement of mining and metallurgical progress in these colonies, that much mutual benefit will ensue. There are many directions in which each body can assist the other, and I trust that a friendly co-operation will be maintained.It is gratifying to feel that in all the colonies a distinct movement is being made to increase the facilities for education in Mining and Metallurgy but if I may refer to our colony of Victoria in particular, we have to express the profound regret that in the means of education in the higher branches, we occupy an inferior position, and it is quite certain that we will continue to do so unless the Government is prepared to subordinate provincial considerations to the weightier.

Jan 1, 1901

By A A. Ndiaye, A Galli

In a companion paper on current hedging practices in the mining industry (Armstrong et al, 2009) we showed that contrary to popular belief, mining groups are still using financial derivatives to hedge against foreign exchange risk and interest rate risk, and more recently against adverse changes in energy prices, notably the oil price. This paper presents a case study on a hypothetical gold mine to illustrate the impact that hedging policies could have on its profitability by reducing the downside risk due to adverse changes in the exchange rate and increases in fuel prices. The characteristics of the hypothetical mine have been set to reproduce those of a real gold deposit, the Kisladag mine that is currently being exploited by open pit methods in Turkey. This mine was selected because its feasibility study was available to the public. Geostatistical simulations are used to reproduce the inherent uncertainty on the recoverable reserves û stochastic simulations are used to generate the variability of the other three key sources of uncertainty: the gold price, the cost of energy and the exchange rate. A simple strategy based on straightforward vanilla options (puts and calls) was developed for hedging the last two risks, on the assumption that the company sells its production at the prevailing spot price.

Jan 1, 2009

By Nicol S. K, Swanson A. R

The poor flotation response of many coals has in the past been attributed to such factors as differences in rank, differences in degree of oxidation, differences in petrographic composition, or slime coatings. The present work shows that while all these factors undoubtedly influence flotation, the size distribution of the feed may override these. Evidence is presented which shows how this factor can lead to substantial losses of coarse coal (>250 µm)from a coal which would normally be considered amenable to flotation. Reasons for this loss of flotation response are suggested together with means of overcoming the problem.

Jan 1, 1978