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By Frank G. Breyer

THE .following developments in the zinc field during 1935 are listed in the order of their importance. Each will he amplified in later paragraphs. In the field o f Metallic Zinc: (1) Construction of further continuous vertical retort smelting capacity in the United States and Germany. (2) Expansion of fractional distillation capacity in the United States. (3) Great expansion in the zinc-base die-casting industry in the United States and abroad. (4) Wide acceptance of heavy galvanizing by the steel industry. (5) Construction of the first commercial wire electroplating plant for putting on heavy coats of pure zinc. (6) Firm establishment and appreciable expansion of the practice of using zinc dust as a reducing agent in the organic chemical industry.

Jan 1, 1936

By G. C. Trevorrow

STRIP mining during 1943 increased considerably with further extension of mechanical loading in mines already partly mechanized; with the considerable introduction of mechanical loading into hand-loading mines; and with improvements in the use of loading equipment. Extension of the use of machinery both in strip mining and underground is due to reduction in labor supply and increased cost of labor, together with the increased demand for coal during the period of labor shortage.

Jan 1, 1944

By P. Somasundaran, G. E. Agar

The role of calcium, phosphate, and fluoride species in determining the zeta potential of apatite in aqueous solutions was investigated in this study. The zeta potential of apatite was determined by streaming potential measurements over a wide range of concentrations of potassium nitrate, calcium nitrate, potassium dihydrogen phosphate, and potassium fluoride solutions at various pH values. While the addition of phosphate made the apatite surface more negative at all pH values, calcium caused a significant increase of the zeta potential only when the zeta potential was negative. Fluoride addition had only a minor effect on the zeta potential, but both negative and positive values were increased.

Jan 1, 1973

By J. A. Vezina

The effects of particle size distribution on metal extraction have been determined from pressure leaching Renzy Mines Limited concentrate with oxygen. Using a pulp density of 30 per cent solids, an oxygen pressure of 80 psig, a temperature of 230°F, a grind of 2.5 hours and a retention of 8 hours resulted in the almost complete dissolution of the nickel and the cobalt and the decomposition of over 96 per cent of the chalcopyrite finer than 20 microns. Only 11 per cent of the chalcopyrite coarser than 20 microns was reduced to smaller than 20 microns.

Jan 1, 1973

By T. E. Wilson

An exploration bore core sample of coal ought to be reduced from its original cylindrical form to a particle size distribution and particle composition that reflects, insofar as possible, a process stream of? raw? coal it represents. Often, coal cores are reduced with a laboratory crushing machine, the product of which may not match the raw coal size distribution or size fraction composition. This study employs drop-shatter impact breakage followed by dry batch tumbling in a steel cylinder rotated about its transverse axis in order to characterize the core material in terms of first-order and zeroth-order breakage rate constants. These are indices of the propensity of the coal to degrade during excavation and handling. Initial drop-shatter and dry tumbling tests were done with synthetic cores, to reduce material variables and . conserve difficult-to-obtain coal cores.? Cores of three different coal beds --Illinois No.6, Upper Freeport, and Pocahontas No. 5 -were subjected to drop-shatter and dry batch tumbling tests to determine breakage response. Comparison of coal preparation plant feed with a crushed bore core and a bore core prepared by drop-shatter and tumbling (all from the same Illinois No.6 coal mining property) indicated that the size distribution and size fraction composition of the drop-shattered/tumbled core more closely resembled the plant feed than the crushed core.

Jan 1, 1998

Some mqre facts and inferences are presented in amplification of a recent paper on the geology of the Kalgoorlie Golden Mile stressing the volcanic origin of its rich gold ores, some of which are considered tobe exhalites. Previously unpublished and largely unmapped pyroclastic features in carbonated and chloritized, but not in amphibolitic, country rock are brought to attention. This applies particularly to the main host, viz. the relatively coarse-grained quartz dolerite greenstone (Q. D. G.), i.e. Golden Mile Dolerite, and gives more credibility to the spatial association of the rich Green Leader and telluride ores with bodies of sediments and tuffites occurring within, or adjacent to, Q. D. G. There may be an intrusive relationship with contiguous mafic amphibolites of doleritic origin, but this is not certain and can only be resolved by morecomprehensive mapping than in the past. Volcanic features have always been recognized in CalC Schist, i.e. Paringa Basalt, more so recently in the shape of coarse volcanic breccia.Iu the subsequent deformation of the gold ores since their inital emplacement there appears to be a structural parallel with some Canadian base-metal deposits, most of them of volcanogenic origin.

Jan 1, 1976

By AIME AIME

THE paper by C. H., Lieb on the "Economics of Oil-Producing Practice" (June issue, M. & M.) contains much food for thought. The engineers should be gratified that an executive with Mr. Lieb's. responsibility should recognize their standing in the industry. Yet after giving them that recognition, he proceeds to spur them on to greater accomplishments by pointing out that their job is only partly done and in some instances poorly done. The operating policies in this paper when applied to new pools with flowing wells are sound. Neither do I take exception to their application to pumping wells. But I do wish to comment on what lie says about price when applied to the many more wells that are approaching abandonment that is, the small producing wells. Mr. Lieb states in effect that higher prices would be detrimental from the long range viewpoint. I doubt that the present prices of crude will provide an ample return from the hundreds of thousands of small wells that have possibilities of substantial recovery by means of water-flooding, repressuring with gas, and air drive. Probably expenditure for experimental work can he justified, but at this time it must usually be considered as experimental. Recently I visited a property where it was estimated that $250,000 would be spent on a 160-acre tract for flooding purposes. The rate of r e t n r n and amount of profit at today's prices are uncertain. It can be argued that if this type of recovery is not economic with crude at $1 then it can he delayed as it is now possible to secure economically an ample supply of crude from our flush fields. But these old fields still retain large quantities of crude in a dormant state, and should not he abandoned per-

Jan 1, 1936

By Kelly J. Driscoll

Impure zinc (98.5%) was electrorefined to high purity zinc (99.995%) using a fused salt electrolyte of molar composition 1: 1 : 1 :2 ZnCI2:KCl:NaCl:LiCl with a current efficiency of about 90% at 723 K. A recessed channel electrorefining cell was developed which achieved excellent mixing of both the metal and the electrolyte and by ensuring a very small anode to cathode spacing the voltage drop across the cell was 0.16 V and at a current density of 7kA m-2. The physical characteristics of the cell were observed using a low temperature model which showed the formation of droplets and rivulets which provided mixing. The application of this approach to the refining of other non-ferrous metals is discussed.

Jan 1, 1992

By F. Tailoka

Bi was electrorefined from alloys containing 10-90 wt% Pb, together with Cu and Ag as minor impurities, in a basic cell and in a recessed-channel cell with 27.5:72.5 NaCl-PbCl electrolyte at 450-470 degrees C and 10 000-20 000 A/m2. The voltage in the basic cell was as high as 9 V, with some carryover of Bi to the cathode observed, whereas in the recessed-channel cell it was as low as 285-635 mV. Flow patterns observed in a room-temperature model indicated that the recesses provide both static liquid hold-up and good mixing of the alloy, enhancing cell performance in combination with the reduced anode-cathode distance of 0.90 mm. The purity of the resulting anode product is as high as 99.9%

Aug 1, 1995

By S L. Nicol, B J. Hogg, O J. Mendoza, S Nikolic, A Burrows

The top submerged lance (TSL) technology, developed in the 1970s, is now widely used for the processing of a range of materials. The key advantage the ISASMELT™ TSL technology provided was the ability to process feed materials in a highly turbulent bath, reaching close to equilibrium conditions, uniquely allowing for operation below the liquidus of the molten slag phase. The details on what happened below the liquidus line in the phase diagram became critical for the successful operation of the technology. During the development of the ISASMELT™ technology this led to a collaboration between the Process Technology group of Mount Isa Mines, now part of Glencore Technology, and the Pyrometallurgy Research Centre (PYROSEARCH) at The University of Queensland. The fusion of the phase equilibria research into the technology development allowed for understanding of the behaviour of molten splash, reliable tapping of the furnace, and the ability to operate the furnace with a refractory lining and achieve a year campaign life in excess of four years. The outcome has allowed for the highly successful adaption of the ISASMELT™ technology to recycling of complex feed streams necessary to drive circularity in our modern global economy.

Aug 21, 2024

By Danyer Girón, Sergio Vicuña

A través de los años de operación en Minera Yanacocha, los minerales se han vuelto más variados y complejos, lo cual genera que los precipitados del proceso Merril Crowe también lo sean. El presente trabajo tiene como objetivo lograr fundiciones más seguras y eficientes, así como analizar la información de los principales constituyentes del precipitado Merril Crowe, a través del desarrollo de un algoritmo de cálculo que determina la proporción óptima de constituyentes de la carga. Se propone una metodología y solución técnica para lograr un proceso de fusión seguro y óptimo, que incluso genera un metal dore más limpio y un proceso de recuperación de oro más eficiente. Asimismo, el algoritmo puede ser utilizado con buenos resultados para la fusión de distintos materiales (con distintas concentraciones de constituyentes), tales como los precipitados del proceso Merrill Crowe, los polvos recuperados de los bag house, la limpieza de sumideros de planta, entre otros.

Sep 20, 2019

By I T. Tshabalala

In typical conventional narrow vein stoping operations, the use of temporary support components to offer some support to workers, whilst the permanent and generally more elaborate support system gets installed or constructed, still results in injuries to people. The authors wishes to explore the probability and practicality of making use of new generation support products to make the support operations safer as well as enhance productivity in the stope face. This paper will examine the use of Autorock Drills as a means to drill roof support holes and install appropriate support components into these holes, as well as the application of ?Thin Spray Liners?, commonly called TSL?s as an additional means of creating a safer operating environment. The installation of netting as a means of roof protection and other support aspects such as cemented roof-bolts will also be explored. These proposed items are envisaged to improve the safety of our people and reduce production down time and increase production and productivity.

Jan 1, 2008

By C Killip

Working in Australia’s harsh climate can have a significant impact on the health, safety and productivity of our teams, but is our working environment expected to be more prone to heat stress in the future? Climate modelling suggests that we are likely to encounter more frequent heatwaves and higher apparent temperature. Does this mean that our teams will be at greater risk of heat stress, and are we prepared to deal with the changes in our future climate and the potential impacts on our working population? This paper will review the recent research on climate and projected changes to all meteorological parameters that are important in understanding the likelihood of heat stress. The paper will also describe the challenges encountered in the management of heat stress in a workforce, and then outline a systematic approach to heat stress management that will allow you to assess your own risk and manage your day-to-day operations into the future.CITATION:Killip, C, 2015. Future climate – is heat stress a real risk for the future and how can we better manage it?, in Proceedings Third International Future Mining Conference, pp 181–188 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By M. R. Stokes

Over the recent years there has been an increase in the application of retreat mining on longwall faces as mine operators strive for ever greater productivity. The purpose of this paper in then to review current practice as a starting point and then move forward to discuss the future geometry's that a longwall face may take. Single and double production zone three roadway faces are assessed. All possible configurations of three roadway faces are defined. Unsuitable configurations are rejected after analysis of broad ventilation issues. The remaining configurations are then assessed on an operational basis, this includes: limits on retreat synchronisation, structure of centre gate, floor bulging and equipment installation. The remaining viable configurations are then further assessed on ventilation issues, this includes: provision for gas control/gas fringe, face climate and balancing of face flows. Possible face climate is assessed using numerical simulation of the various configurations, the predicted dry/wet bulb temperature and predicted levels of heat stress indices are given and discussed in detail, along with face flow balancing. The necessary conditions required for the successful operation of a double production zone three roadway face system are formulated, together with conclusions as to the possible level of application.

Jan 1, 1997

By Van Heuzen JA

The extensive deposits of brown coal in the Latrobe Valley form the major solid fuel resource in Victoria and are the energy source for most of the State's power generation. This paper describes the coalfield resources allocated for electricity generation and a potential sequential develop- ment of these areas in future years to supply future power stations.

Jan 1, 1982

By L. Kovisars, F. Buttazzoni

The current demand for copper in the western world exceeds 7 million tonnes annually. The growth in demand is expected to average 2.6% annually to a level exceeding 11 million tonnes in 2000. Copper mine production is currently about 6 million tonnes annually; the annual net addition to mine output in the future will have to average about 190,000 tonnes of contained copper. The industrial nations of Europe and the western Pacific are heavily dependent on copper imports. Currently these import needs are supplied by Canada, Africa and Pacific producers. The increased demand for copper in the future is expected to further weight the trade balance to the Pacific suppliers. An evaluation of undeveloped deposits allows the ranking of these deposits based on total cost of production, including provision for plant and infra- structure investment as well as political/social/ economic risk. Peru, Canada, and the Southwest Pacific are expected to significantly increase exports. The United States will develop deposits to replace depleted mines, maintaining mine production at a level approximately equal to current output, with a consequent increase in copper imports. Chile is expected to become the world's leading copper producer, as well as expanding it's position as the leading exporter.

Jan 1, 1982

This talk was delivered in Kalgoorlie in April this year, to the Kalgoorlie Branch of The Institution of Engineers, Australia. We believe it is of such interest to members of our Institute and readers of this publication we believe it important to extend the audience who have the opportunity to read it. An edited version follows:"Why should we be so concerned about Mining Related Education; after all is said and done, the mining industry is not a great employer of persons?"The mining industry is capital rather than labour intensive. It employs only 2.7 per cent of the national workforce. However; the minerals industry is Australia's major exporter accounting for over 40 per cent of the nation's total export of goods.In Western Australia the value of minerals production in 1985 was about $5,000 million and consequently mineral exports accounted for about 53 per cent of the total value of overseas exports from the State. The diversity of the mining industry is also worthy of mention and produces iron ore, alumina, gold, nickel and mineral sands. That apart, our potential to become a major producer of diamonds, rare earths and petroleum products is considerable, not to mention base metals (copper, lead and zinc) and uranium.Our mining industry is of national importance and contributes in excess of 30 per cent of the total value of Australian overseas trade. Although the mining ind ustry does not employ many people, the people it employs contribute very much more, per capita, to the wealth of the nation than do employees in any other sector of our economy.No-one would deny that during the 20th century Australians have depended on the export earnings from the sale of relatively unprocessed agricultural products and more recently the sale of relatively unprocessed minerals for their standard of living.Not surprisingly, therefore, our economy is highly vulnerable to unstable world commodity market prices.The slump in trade we are currently experiencing (in first quarter 1987-Edition) was brought about by the over supply of the raw materials we produce. However, the recent downturn in world market prices is more serious than previous slumps because in part it is due to technological advances 'in other countries which could have a permanent effect on the world trade of primary products.

Jan 1, 1987

By A Brodbeck, AT Spathis

Australian regulatory control of ground vibration and airblast arising from mining, quarrying and civil construction operations is spread across a number of federal, state and local authorities and across a number of departments with various jurisdictions. The Australian Standard AS 2187.2 contains an informative appendix on damage-related criteria and it is the primary reference for the regulators. The complete standard and the informative appendix is currently undergoing major revision with a focus for the latter on implementing frequency-dependent criteria for ground vibration. Certain directions for change have been raised for consideration by the standing committee, ranging from fundamental issues of measurement and interpretation and others that overlap human comfort criteria. It is anticipated that some of the suggestions will eventually make their way into future standards after an adequate period of consultation and consideration by both the Australian public and others involved in the associated industries.

Jan 1, 2005

By Hatherly P, Holt GE, McNally G

The current methodology for delineating and subsequently evaluating coal reserves is based on the use of vertical drill holes and surface based geophysics/geology. These techniques have three major problems, these being respectively:-a) Vertical drill holes can only provide a small sample of the coal seam and stratigraphy. Therefore the planar variation in coal reserve and environment parameters can only be approximated.b) Although surface based geophysics has had its fair share of success in recent years, there are still environments which have masked the finding of major structures.c) Access to drill sites is difficult at some locations due to mountaineous terrain, standing water and environmental impact.

Jan 1, 1985

By J Johansson

The aim of this paper is to discuss how to form work and organisations in the mines of the future. The Kiruna underground iron ore mine in the far north of Sweden is used as an example on how technical development affects organisational issues like skills, work identity and gender. Over a period of 50 years one can see a transformation of work from manual underground work to automation and remote control from surface level. What characterised the old underground workface was the close relation between man and the hard rock and with arduous physical work under dangerous conditions. Today, the face miners are located on the seventh level of an office building close to the mine. There is also an emerging, and in many aspects already evident, knowledge transformation û from the old and obsolete physical and tacit knowledge and skills (for example the ability to æread the rockÆ) to something new, which can be described as abstract æhigh-techÆ knowledge and skills. The modern technology has created a new type of work û new in terms of competencies and knowledge as well as workload and organisation. At the same time the mining company are recruiting more women and promoting the former pure male work as attractive workplaces for both women and men. All this has effects on how individuals and company create and recreate skills, identity and gender. To some extent the technological development predestines these changes, but there are some choices to be done when forming good work and organisations for the mines of the future. The traditional mining workplace culture and behaviours and the old type of masculinity, the æmachoÆ style, will be challenged by the new æhigh-techÆ work and new competency demands. The changes risk meeting restoring responses, which can have negative impact on the performance of the organisation, for example making it inflexible and perhaps ælaggingÆ behind the technological development. These questions need to be handled when planning future mining.

Jan 1, 2008