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Education for the Mineral Industry in Australia developed in an uncoordinated but effective fashion till the mid 1960's, with recognised quality in graduates, with output matching demand, and with industry needs being fulfilled. Then in the space of a further 20 years, as company structures expanded, as the number, complexity, and costs of mineral projects escalated, as educational facilities, costs and politics increased, as community perceptions and aspirations changed, as government control of minerals and education increased, and as mineral sales cycles and markets fluctuated widely, the very fabric of Australian Mineral Education fell in tatters. Extractive Metallurgy Education suffered most in this collapse, and no compre- hensive remedies have been initiated. We are all the losers. In the 1990's, the extraction of Australian minerals and metals will increase in international significance, and the education of Extractive Metallurgists must meet this need. After examining the current situation, a series of management strategies are proposed to enable Extractive Metallurgical Education to survive and prosper in the next two decades and beyond. These strategic proposals involve industry, the government, the educational bodies, and individuals, in a range of short and long term objectives, policies, and actions.

Jan 1, 1984

By R. C. Gilmore, S. A. Lolon, G. E. Bogin, S. A. Saki, J. F. Brune, J. W. Grubb

"Gob ventilation boreholes (GVBs) are widely used in underground coal mines for longwall gob degasification purposes. GVBs are often drilled within 10 to 30 m above the top of the coal bed into the fractured zone, completed with 20 cm (8 in.) diameter casing and 60 m of slotted pipe at the bottom. The purpose of this completion strategy is to create a pressure sink to capture the emissions before they can enter into the underground workplace. For GVBs to work effectively, they must be drilled close enough to the working areas to capture methane from the fractured zone while the setting depth must be kept above the caved zone to minimize the amount of ventilation air that is drawn into the GVBs. Well completion parameters are important for creating safe working conditions. In this paper, computational fluid dynamics (CFD) studies will be presented to analyze the effect of different practices for GVBs completion parameters for methane extraction, formation of explosive gas zones in the gob and methane concentrations at the longwall face and tailgate. Authors have identified the optimum completion parameters for GVBs, which can maximize the benefit and minimize fire and explosion risk. INTRODUCTION Coal mines may be considered gassy based on the presence of CH4. Gas from the mined coalbed or from rider seams above or below the mined coalbed can migrate into the gob and then potentially move towards the working areas. In longwall coal mines with high methane emissions, sufficient ventilation and additional methane control measures are usually required to reduce the methane concentration in working areas to below statutory levels. Several techniques or combinations of techniques are available to control the methane hazard. These may include mine face ventilation to dilute methane, coal bed degasification, nitrogen injection into the gob to render a methane atmosphere inert and the use of gob ventilation boreholes (GVBs). Longwall face ventilation and dilution alone can only handle methane emissions up to a certain amount. When methane emissions exceed the face ventilation capacity, additional control measures are required. Drilling horizontal or vertical methane drainage holes into the coal seams as well as gob ventilation boreholes from the surface into the gob area to extract methane are common practices. GVBs are usually drilled from the surface above the longwall panel ahead of mining. When the face moves outby the GVBs and the gob begins to form, methane production starts from the boreholes. It is important to control the performance of GVBs to maintain a safe working environment in the mine. The performance of GVBs depends on multiple factors, including borehole location, length and diameter of slotted casing, setting depth of casing above the coal seam being mined, wellhead vacuum pressure, and permeability of caved-fractured zones."

Jan 1, 2016

By Jackson G. Jenkins

Magma Copper Company's San Manuel SX-EW facility has operated since May, 1986. The original facility had a design capacity of 25,000 tons per year of electrowon copper cathode produced by processing pregnant leach solution from an open pit/heap leach operation. In 1988, the plant was expanded to 50,000 tons per year to incorporate processing in-situ leach solutions. This paper focuses primarily on the heap leaching area with regard to exploration, testing, feasibility, permitting, design and construction, and operating practices. Research utilizing surfactant leaching aids to enhance copper recovery is also discussed.

Jan 1, 1993

By Daniel Proszek

A globalização tem tornado o mercado internacional mais competitivo e o setor brasileiro de fundição cada vez mais é ameaçado pela produção asiática que oferece produtos com custos inferiores aos valores nacionais. O meio ambiente é outro fator emergente nos panoramas atuais, empresas com consciência ambiental sofrem com elevados custos para a disposição correta de materiais. Estes fatores são abordados no atual trabalho que focou na adequação de equipamento para regeneração mecânica de areia, tornando possível a reutilização do principal consumível de moldes de fundição. Tendo como base projeto inicial de equipamento de regeneração mecânica, foram aplicadas melhorias e posteriormente foram trabalhadas variações de parâmetros do processo. Oriunda do processo de cura a frio, a areia fenólica usada destorroada industrialmente foi testada variando a velocidade de rotação do atritor (450 e 900 RPM), e o tempo de permanência (10, 20 e 30 min). Os experimentos em areia foram analisados através de distribuição granulométrica, análise de perda ao fogo e também a limpeza dos grãos via microscopia eletrônica de varredura, sempre guiados pelas referências de areia base e areia destorroada. Analisando os resultados encontrados foi possível identificar a influência das variáveis testadas e assim determinar a configuração mais eficiente na limpeza da capa resina que envolve grãos.

Aug 8, 2018

By T. A. Penzov

As a result of recent scientific and experimental studies new technical devices have been developed for monitoring and control the process of grinding. The description of microprocessor module MILLCONT 1 for control of the loading of the mill and microprocessor density control module DENSIMETER is given in the paper. The improved variant of the automatic system for ore grinding control in single-stage ball mill working in close cycle with a classifier with above mentioned technical means is shown in the paper. The loops for measuring and stabilization of the basic technological parameters (density of the ready pulp ? and fineness of grinding of the pulp ß) are described in the paper. The nowadays economic results in ore grinding process automation are given as well.

Jan 1, 2014

By V. Z. Kozin, E. A. Bekchurina, P. S. Volkov, Yu. P. Morozov, A. S. Komlev

"The current sampling systems of ore flows or concentrates are based on the method of cross sections in point sampling and the method of scooping in reducing. The limited number of point samples in sampling and microsamples in reducing lead to big random and probable systematic errors. The paper defines the principles of sampling, which assure the absence of systematic errors and also provides calculation formulas of probable errors in sampling methods of cross and longitudinal sections as well as in samples preparation. The article sets the fundamental laws of sampling: the dependency of minimal mass of gross sample and number of point samples from mass of point sample in sampling from heterogeneous body; the dependency of a sample minimal mass from lumps’ size in preparation of carefully mixed samples; the dependency of point samples’ dispersion from duration of control period. The paper introduces the fundamental notions: lump variance; probable systematic error; methodical error. It also provides a solution of outstanding sample correct application in analysis results calculations. In application of automatic analyzers, mounted in material flows, the probable error connected with sampling, is calculated by the formulas for carefully mixed sampling bodies. The paper describes the developed and introduced sampling systems on the base of combined application of cross and longitudinal sections methods in sampling and preparation of samples. The advantages of this equipment are compactness, reliability, simplicity in service and operation, and for pulps it is adaptability in pipelines. Application of the developed equipment entirely excludes probable systematic error. The new systems of sampling and preparation of samples are introduced at 25 concentrating plants. Introduction of the developed systems at sampling balance points of concentrating plants allowed double reducing balance deficiency."

Jan 1, 2018

By R H. Boffey

The Osborne copper-gold deposit was discovered in North-West Queensland in 1989. Underground production activities commenced at Osborne deposit in April 1996. This paper will examine technical and operational aspects of the underground mine during its development to a 1.2 Mtpa operation . Technical aspects discussed include geology, mine design and mining methods, equipment fleet selection and capital infrastructure. Operational aspects discussed include the evolution and performance of the integrated work teams that are utilised at Osborne to perform all mining and maintenance activities.

Jan 1, 1998

By Laurindo De Salles Leal Filho

Microflotation tests with sodium oleate, in alkaline pH, were performed with apatite and some silicates (phlogopite, quartz, and chlorite) that commonly occur in Brazilian phosphate ores. Further flotation tests were carried out with selected ores containing the same silicates as important gangue minerals. The results showed that apatite recovery is highly affected by competition with silicate minerals, probably activated by calcium ions dissolved in flotation pulp. Inorganic chemical species (sodium tripolyphosphate, sodium carbonate/ bicarbonate, and carbon dioxide) that could act as water softeners were used as modifier agents. They proved to be capable of improving flotation recovery and selectivity.

Jan 1, 1999

By R. J. Gochin, M. A. Diaz, M. L. Court

Single impact breakage tests have been carried out on samples of alumina in carefully controlled atmospheres consisting solely of nitrogen gas and water vapour. The results indicate a statistically significant increase in the surface area of the progeny particles as relative humidity rose to 50%. The majority of this increase was found to occur under conditions when adsorption was a monolayer or less. The results are consistent with the theory of surfactant-induced strength reduction of materials proposed by Rehbinder and Westwood. There are important implications where single impact tests are used as part of a design methodology for comminution machines. In most procedures relative humidity has not been a controlled variable.

Jan 1, 1995

[The development of economically effective and safe methods of mining thick coal seams enables to involve considerable coal reserves into the energy resources in different countries all over the world.]

Jan 1, 1975

By J. M. Floyd

The theory, construction and applications of oxygen sensors employing high-temperature electro- chemical cells with solid electrolytes are briefly reviewed. The application of disposable probes to measurement of the oxygen potential in matte and slag baths in tin, copper, and nickel smelting operations is described. Examples discussed include end-point determination in smelting and slag-cleaning operations, pilot-scale investigations of process chemistry to assist in the development of smelting strategies, and measurements in operating smelters to improve the efficiency of operation.

Jan 1, 1984

By Tim Wolf

The author has seen an increased use of shaft-mounted, right angle drive assemblies. These designs use the pulley shaft as its 'foundation" and can create significant overhung loads. To reliably perform, the pulley and shaft must be designed for these special requirements. This paper will focus on the development of overhung loads and their design effects. Special considerations to maximize performance will be presented and comparisons with other drive options will be made. Experience in heavy mining applications will be used throughout.

Jan 1, 2000

By Stephenson IM

Research to develop the use of L.D.slag as an aggregate in road construc-tion is described. The chemistry and mineralogy of L.D. slags are shown to be generally similar to S. Yorkshire arc furnace slags, which have been success-fully used for road construction for many years, although both free lime and iron contents were found to be higher. Physical and mechanical properties are good but the slags' high density will result in lower "covering capacity"."Weathering" in stock piles is shown to significantly reduce free lime levels fairly rapidly although around 50 per cent of the mean "fresh free lime" content is still present even after two years treatment.

Jan 1, 1979

By Irina A. Pulyaeva

Hydrogenetic Fe-Mn crusts are ubiquitous in the ocean basins and play an important role in marine mineral-deposit research because of their widespread occurrence and high concentrations of valuable and rare metals. Directed research, which started in the last quarter of the 20th century, has provided significant results, with substantial amounts of data produced on Fe-Mn crusts structure, composition, and distribution in the global ocean. Detailed study of several seamounts has given confidence about the scale of Fe-Mn crust development and their characteristics. Now, commercial interests gain more and more attention. However, at the same time some theoretical questions related to Fe-Mn crust history including controls on metal sources and concentrations have not yet been answered. Here, we present the overview of age, composition, distribution, and geological setting of hydrogenetic Fe-Mn crusts from Pacific and Atlantic seamounts and discuss the geological evolution and conditions that led to the formation of potentially economic concentrations of metals. The age, composition, and distribution of Fe-Mn crusts in the Atlantic and Pacific oceans were determined by using a Fe-Mn deposits database compiled from our original data, published papers, published databases, and other international sources. Comparative analysis of Fe-Mn deposits from the Atlantic and Pacific oceans shows that there are similarities in basic characteristics of crust formation in both oceans. Simultaneously, there are significant differences in the scale of Fe-Mn crust distribution and composition that can be explained by differences in geological settings and characteristics of the deposition environment.

Jan 1, 2011

By Allen D. Garrison

The chemistry of clays and shales has been assuming increasing importance in the petroleum industry, and two factors have greatly influenced this trend. The first has been the growing evidence that the marine shales are source beds, and that the petroleum compounds have migrated to the sand reservoirs overlying or underlying these shales: the second has been the demand for drilling fluids better adapted to penetrate these marine shales without difficulty and expense. Origin and General Composition of Clays and Shales Clays, shales and surface soils are all closely related materials. They are mixtures of finely divided compounds formed during the weathering of the solid crust of the earth. Their nature is essentially colloidal; that is, their behavior is determined by the state of division of the materials and the surface reactions of the smallest grains. Many of their chemical changes affect only the exposed areas and do not involve the interior of the grains of matter. The extent of these reactions is more nearly proportional to the area of the substances than to their mass, therefore it is possible for a small amount of a material in an extremely fine state of division to completely dominate the character of the mixture. More than 83 per cent of the crust of the earth is composed of three elements—oxygen, silicon and aluminum. Consequently, the corrosion products of the crust are predominantly aluminosilicates, or compounds of aluminum, silicon and oxygen. If we add the compounds of six elements—iron, calcium, sodium, potassium, magnesium and hydrogen—more than 98 per cent of the crust has been accounted for. These six elements, together with the first three, also appear in soils, clays and shales. But direct chemical analysis is of little value in describing the nature of such materials. Many chemical individuals may be present in variable amounts, and the extreme subdivision of any one of the individuals may contribute qualities that dominate the mixture.

Jan 1, 1939

By C. W. Drury, E. J. Hall

The iron-nail method of assaying has been used for a number of years, but has not met with the approval of all assayers. The method possesses advantages which may be given as follows: (1) no preliminary treatment is required; (2) a lead button of proper size can be obtained; (3) it is economical. On the other hand, it has its disadvantages, which may be summed up as follows: (1) it is not applicable to ores containing large amounts of impurities other than sulphur, as practically all the base metals will contaminate the lead button ; (2) the slag is unsatisfactory in the larger number of fusions; (3) the method was known to give low silver results under certain conditions and the gold results were questionable. It was with the idea of determining the extent of this latter disadvantage that the following investigation was undertaken. It is well known that the fusion obtained in the lead assay is far more satisfactory than that in the " nails method" for gold and silver. The principal difference in the charges as a class is the presence of considerable reducing agent in the lead charge, and a limited oxidizing action in the nails charge, dud to PbO. The possibility of improving the nails fusion by simulating the lead charge was the reason for using argol in some tests, even though there were reasons for expecting this would have an objectionable effect on the results. Preparation of the Gold-Bearing Material. The materials containing gold and silver used in the following experiments were prepared rather than selected, in order to have a definite working product excluding undesirable elements. A high-

Jan 1, 1914

By Allen D. Garrison

The chemistry of clays and shales has been assuming increasing importance in the petroleum industry, and two factors have greatly influenced this trend. The first has been the growing evidence that the marine shales are source beds, and that the petroleum compounds have migrated to the sand reservoirs overlying or underlying these shales: the second has been the demand for drilling fluids better adapted to penetrate these marine shales without difficulty and expense. Origin and General Composition of Clays and Shales Clays, shales and surface soils are all closely related materials. They are mixtures of finely divided compounds formed during the weathering of the solid crust of the earth. Their nature is essentially colloidal; that is, their behavior is determined by the state of division of the materials and the surface reactions of the smallest grains. Many of their chemical changes affect only the exposed areas and do not involve the interior of the grains of matter. The extent of these reactions is more nearly proportional to the area of the substances than to their mass, therefore it is possible for a small amount of a material in an extremely fine state of division to completely dominate the character of the mixture. More than 83 per cent of the crust of the earth is composed of three elements—oxygen, silicon and aluminum. Consequently, the corrosion products of the crust are predominantly aluminosilicates, or compounds of aluminum, silicon and oxygen. If we add the compounds of six elements—iron, calcium, sodium, potassium, magnesium and hydrogen—more than 98 per cent of the crust has been accounted for. These six elements, together with the first three, also appear in soils, clays and shales. But direct chemical analysis is of little value in describing the nature of such materials. Many chemical individuals may be present in variable amounts, and the extreme subdivision of any one of the individuals may contribute qualities that dominate the mixture.

Jan 1, 1939

By G Newling

Zinifex Rosebery Mine is a lead-zinc underground mining operation located at the base of Mount Black, on the West Coast of Tasmania. Mining activities at the Rosebery Mine have been undertaken for over 100 years, and it has been operating in its current form for over 60 years. A large surface and underground exploration drilling program over the last 18 months has increased the mineÆs expected mine life from five to 12 years, with expectations that over the next 18 months as the program continues this will swell to 20 plus years. Zinifex Ltd secured Rosebery Mine in April 2004 and commissioned a detailed life-of-mine (LOM) study on all aspects of the operation. One of the most detailed sections of this report was on the state of the current ventilation system. It was identified in this report that for mining at the current depth of approximately 1100 m to continue a minimum 30 per cent increase in ventilation quantity was essential, as well as a likely requirement for a refrigerant cooling plant for each of the two deepest panels, the K and P lenses. It was identified that Zinifex did not have personnel with the expertise in underground refrigeration to manage and implement a project of this nature. A second report was commissioned with Bluhm Burton Engineering (BBE), a South African firm specialising in both surface and underground large-scale refrigeration plants. BBE concluded that two refrigeration plants were required to provide the necessary cooling power in the lower sections of the mine. In 2005, with BBE as technical consultants, Zinifex Rosebery Mine embarked on a project to commission two underground refrigeration units capable of lowering the wet bulb temperature at the decline face by four degrees centigrade. This paper is intended to give the reader an overview of: Rosebery Mine operations,Rosebery underground refrigeration project,technical difficulties associated with implementing an underground refrigeration system, andkey learnings to date.

Jan 1, 2008

For many years the occurrence of gold in the Coeur d'A1ène region had been rumored among the pioneers of the Northwest. It is stated that as early as 1853 gold was discovered in this district by Donelson, of the Stevens expedition, but the hostility of the Indians prevented prospecting. In 1858, when Lieutenant John Mullan surveyed the military road across the Bitter hot mountains, the members of his expedition, most of whom had mined in California, noticed sundry outcrops of good-looking quartz, and some of them actually found gold, as is recorded in a letter that Mullan wrote, from Washington, in 1884. The first successful prospector in the Coeur d' Alène was Tom Irwin, who worked a quartz vein on the Mullan road in the spring of 1879. Two years later he met A. J. Prichard, who was engaged in the lumber business; he told him what he thought of the chances of placer mining in the upper reaches of the Coeur d7AlBne river. This was in 1881. Prichard became keenly interested, and himself found gold on several creeks, one of which is now known by his name, at a place close to the site of the town of Murray.* In 1883 Prichard located a number of claims, and shortly afterward he wrote a letter to the members of a Liberal League to which he belonged, inviting them to "secure the lion's share" of the mineral wealth he had uncovered. His letters caused a stampede from Montana and Colorado, and from South Dakota also, to the Coeur d'Alène gold belt in the summer of 1883. A town, named Eagle City, was surveyed; in 1884 lots sold at prices ranging from $200 to $2000. The buildings were made of logs and shingles. Shoveling of the snow in' front left s

Jan 1, 1932

By Clinton Strachan, Rob Dorey

10.1 INTRODUCTION This chapter presents considerations which should be applied to heap leach pad site selection, site evaluation, and design, relative to the geotechnics of the site and ore. 10.1.1 General Guidelines are presented covering the topics encountered in design and construction of heap leach faci1ities. Because geotechnical characteristics vary from site to site, not all geotechnical topics associated with a specific heap leach facility are presented, and there may be exceptions to some of these guidelines. The general features of a heap leach facility (from Chapter 1) to be discussed in this chapter are: • Leach pad (including leach pad foundation and liner); • Heap; • Solution storage faci1ities (for pregnant and barren process solutions) ; and • Solution collection facilities (which collect and convey solutions in the heap and convey them to solution storage facilities). These general features are illustrated in Figure 10.1. Liners for these facilities are discussed in Chapter 11. Solution application systems and the sizing aspects of solution storage facilities are discussed in Chapters 6, 7, and 12. The general features listed above are constructed with and overlie naturally occurring materials (such as ore, borrow soils, and subsurface soils and rock). These natural materials are relied upon to perform in an acceptable manner as a component of the leach facility (such as the liner, drain material, and foundation).

Jan 1, 1988