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By Edward J. Caldwell

In 1930 the Bureau of Mines published a description3/ f the concentrating process of the Magma Copper Co. as it had been developed to that time and was then employed. The prevent paper revises the description to the end of 1943 and includes a description of the smelting processes. Data from the mild and smelter operations for, 1942 are given in tables 1 to 14, Billing costs are included, but it is not permissible to publish smelter costs.

Jan 1, 1944

Raw materials account for over 60 per cent of the cost of hot metal production in classical blast furnaces and the principal cost component is cost of coke. Dependence on coke is a traditional weakness of blast furnace ironmaking and while efforts have been made to evolve alternative ironmaking technologies which do not use coke, such as direct reduction, smelting reduction, and the more recent method of making iron carbide, blast furnaces continue to be the most efficient means of producing bulk hot metal even today. Coal injection, to the extent of 150 - 200 kg/t of hot metal, has been one of the major innovations made in blast furnaces to decrease cost and to reduce the dependence on coke. This has, however, given rise to more stringent coke property requirements (which often means more expensive coke) - a `tail spin' of Sorts!

Jan 1, 1999

By Natalya. N. Ankusheva

The problems of ore-bearing palaevolcanic structures in folded belts are actual because of their high productivity in nonferrous, ferrous and noble metals ores. Now relationships of location and conditions of formation for sulfide-massive and gold-bearing deposits are investigated very well in Urals. But carboniferous sulfide-barite mineralization, for example the barite veins in Arcaimsky palaevolcano are?nt studied enough now [3-5]. The purpose of this research is the studying of mineralogy and thermobarogeochemistry of barite from the hydrothermal veins. It will allow to determine the conditions of its formation and to compare it to the similar mineralization of others ore types.

Jan 1, 2006

By C. Bazin, D. Hodouin

"A flexible model involving perfect mixers, stagnant zones, plug flow, material bypassing and recycling zones has been developed for interpreting mixing phenomena in mineral processes. The mixing properties are described by the residence time distributions which can be subsequently interpreted by the flexible model. User-friendly computer programs (for 1MB-PC or compatible) have been developed for simulation and modelling of RTDs using the proposed model. Seven mineral processing case studies are discussed in terms of experimental procedure, model calibration results and application of the estimated mixing model to process modelling, diagnosis, and performance evaluation. IntroductionIn any mineral processing plant there are continuous-flow machines that transform or separate the ore components. Grinding mills, flotation cells, conditioning and leaching tanks are examples of such machines. The performances of these vessels or reactors are controlled by the rate at which the reaction proceeds and the time spent in the environment where the reaction occurs. This paper deals with the latter aspect of mineral processes operation.Since most of the reactions occurring in mineral processing units are time dependent, knowledge of the residence time of the material in process vessels is important for modelling and diagnosis purposes. Due to the random mixing phenomena involved in the process equipment, there is a distribution of the residence time of the ore particles and the fluid in the vessel. The probability density function E(t) that a micro-element of the material flowing through a processing unit stays a time t in the vessel, is the residence time distribution (RTD) of the corresponding component."

Jan 1, 1988

By Cordner G. D

Titanium is not yet being produced on a commercial scale despite the facts that it has some impressive properties, and that it occurs very abundantly in easily-mined, highgrade oxide ores. One important reason for this is that the excellent mechanical properties of the metal were not widely recognised and appreciated until about twenty years ago.Another factor which has tended to retard progress in titanium metallurgy has been the realization that the oxide minerals of titanium are very stable; in other words, considerable energy has to be expended to reduce the oxide to metal. Table 1 presents the minimum energies which would have to be expended to produce one ton of each of the metals, aluminium, magnesium, titanium and iron from their respective oxides under theoretically ideal conditions at normal temperature and pressure. At higher temperatures, the minimum energy requirements are different, but the values for the various metals still fall in the same order as indicated in Table 1.In actual fact, the energy consumption in the case of any particular metal is higher than the ideal value by an amount which can be determined only by' the results of plant practice. The only general conclusion that can be drawn from the data in Table 1 is that it might eventually prove...

Jan 1, 1950

By D. E. Stephenson. Discussion by R. G. K. Morrison, L. Obert

R. G. K. Morrison (Chairman, Dept. of Mining Engineering and Applied Geophysics, McGill University, Montreal, Que., Canada) - The discing of drill core has been a recognized pressure phenomenon for many years but only recently has an interest been taken in the mechanism involved. The work of Jaeger and Cook is referred to in the text. The authors have now advanced the study to establish, within certain loading limitations, a direct relationship between axial and radial stress at failure. This is an important contribution. In mines generally, where pressure conditions result in the spalling of openings, the faces of drifts and crosscuts, on scaling, usually show a concavity with respect to the opening very similar to the face of the drill hole after the separation of the stub. The same holds for shaft sinks. This suggests a similarity between the mechanism of the discing of core and that of the spalling of an opening, under pressure, to develop a more stable outline. The latter, commonly regarded as shear, is the most conspicuous type of failure observed in

Jan 1, 1967

By R. F. Lynch, F. E. Goodwin, A. F. Skenazi

"The Gal/an alloy has been developed for continuous galvanizing of steel. The choice of the eutectic zinc-aluminum alloy with addition of misch metal gives a coating with specific characteristics as far as structure, analysis, surface chemistry and surface morphology are concerned. The performance of the uncoated Galfan coating is superior when compared to conventional galvanized particularly for corrosion resistance and ductility. For coil coating applications, these two assets are of the utmost importance but in order to benefit from these two advantages, good paint adherence and high resistance to edge creep and blistering have to be obtained. Despite Galfan's unique features compared to other zinc based or aluminum zinc based coatings, existing pretreatments and painting conditions are used with only minor modifications in order to assure good adherence and edge creep resistance. With compatible processing, Galfan can outperform galvanized and Galvalume as a substrate for coil coating as is demonstrated with various test results.IntroductionThe technical and commercial development of Galfan, a 95% zinc-5% aluminum-0.1% lanthanum-cerium hot-dip coating for steel, has been rapid. From its identification as a promising coating in late 1980, it has evolved from a research product to a fully commercial product with over 100 000 metric tons of coated sheet produced to date, and another 90 000 tons, at minimum, scheduled for 1986. The great majority of tonnage produced to date has been coil coated for use in building panel , appliance, and similar applications. Much technical work has been done to determine the suitability of Galfan for these applications and the proper way of processing sheet for best results. The present state of knowledge is discussed in this paper, along with some recent applications which are given asexamples"

Jan 1, 1987

By D. Laguitton, D. Hodouin, V. K. Gupta, R. Spring

"The CANMET SPOC project aims at inducing progress in process evaluation and optimization by developing user oriented software based on state-of-the-art theory. The present work is the result of a joint effort by CANMET, Noranda Mines and Université Laval to develop two computer packages: one (RTD) to calculate the residence time distribution that best describes the material transport through the mill, the other (FINDBS) to estimate the rate of breakage and distribution function of the population balance model in a ball mill. The RTD package can handle data from various experimental methods (impulse or complex tracer feed, with or without recycling, etc...). The FINDBS package provides options for the functional description oj both model parameters Band S. The full detail of the methods and programs appears in a users guide. The program capabilities and several sample runs are presented.IntroductionSimulation of mineral dressing operations by computer has been largely contained within academic and research circles and has not yet gained a status of routine practice in the ore and coal industries. It is however a matter of time before process simulators are available on every process engineer's desk to assist process optimization tasks, flowsheet design and professional training. The CANMET SPOC project (Simulated Processing of Ore and Coal) was initiated in 1980 to assist the Canadian industry in integrating computer-based methodology for process evaluation and optimization(1). Software development, documentation and transfer is one of the main priorities of the project which will mature in 1985 by releasing a complete package of manuals and programs covering sampling, material balance computation, unit modelling, flowsheet simulation and optimization . This paper is a condensed description of a typical project element in its 1982-1983 state of development. The required methodology for ball-mill modelling and simulation was consolidated an d merged to other project elements during a joint study under contract financed by CANMET and Noranda Mines Ltd . The first part of the study dealt with documenting experimental methods and software for ball-mill computer simulation. Université Laval GRAAIM (Goupe de Recherche en Automatistion Appliquée à l'Industrie Minérale) acted as sub-contractor for this part of the study(16,17). A second part dealt with applying the model calibration techniques to a large industrial data base and is reported elsewhere(2,18,19)."

Jan 1, 1984

By J. N. Murphy

The use of the National Science Teachers Association (NSTA) regional meetings as a forum to educate teachers on the role of minerals in our society has been immeasurably successful. Each year, on average about 3,500 to 4,000 teachers participate in each of the three regional NSTA meetings. At each of these meetings, nearly 2,000 teachers visit the “Minerals Coalition Booth” and receive free mineral samples and other educational support materials. Some rules of thumb for a successful booth at the NSTA are provided. Considering the level of effort for such a booth, are there alternatives? The NSTA also organizes a national annual meeting with attendance of about 20,000. All who have participated in a regional NSTA agree that the traditional approach of providing a mineral set and teacher materials for a substantial fraction of the 20,000 attendees is not feasible. Conceptual alternatives for minerals education at the national NSTA meeting are introduced and evaluated.

Jan 1, 2001

By Olliver J. G

Over 400,000 tonnes of kaolin, sillimanite, mica, kyanite, feldspar and rutile have been mined from the unique Williamstown orebodies since their discovery in the early 1900's. Numerous companies; both large and small were associated with the early development of these deposits but since the formation of Australian Industrial Minerals in 1947, this company has been the only significant producer. A combination of mining and management problems almost forced closure of the mine in the late 1970's but this was averted by a changed attitude towards mine planning. Mine development is now based on detailed geological and technical investigations, exploration for additional ore reserves is being conducted and laboratory and pilot scale studies are being undertaken to utilise both low grade ores and waste materials. The professional approach to mine and market development will ensure that Williamstown mineral products will continue to be available for many years.

Jan 1, 1989

By Denis Labrie

Le minage en profondeur sous contrainte modérée à élevée présente de nombreux défis aux opérateurs et aux ingénieurs de mine notamment au niveau du contrôle de terrain et de l?environnement minier souterrain, pour assurer la sécurité des travailleurs sous terre et la continuité du cycle d?opération. Des conditions de contrainte élevée signifient une pression accrue au front de taille et sur les structures minières tels les piliers de mine et les fins de zone, un risque de rupture violente ou de coup de toit plus élevé, des zones de rupture plus grandes au pourtour des excavations, des charges accrues sur le support de terrain, etc. Le présent article fournit un aperçu du travail fait à l?intérieur du Programme de Contrôle de terrain de CANMET au cours des sept (7) dernières années, entre 1995 et 2001, pour comprendre et suivre l?évolution des niveaux de contrainte à l?intérieur des structures minières. Les propriétés déterminées en laboratoire sur des échantillons rocheux et les prévisions effectuées au moment de la conception sont comparées avec les observations effectuées en chantier à la paroi des excavations et à l?intérieur de la masse rocheuse. La plupart des cas discutés ici montrent une corrélation satisfaisante entre les observations effectuées en chantier d?une part, et les résultats d?essai obtenus en laboratoire et les calculs réalisés lors de la conception d?autre part. Ces observations peuvent donc être considérées comme des moyens relativement sûrs pour vérifier et suivre l?évolution des niveaux de contrainte présents à l?intérieur des structures minières.

May 1, 2002

By María Julia Ubillús Mellet

El presente texto complementa el estudio de las estrategias de seguridad en las empresas mineras a través de la alienación de las herramientas de gestión humana en una cultura de seguridad y prevención competitiva, de forma que se mejore el estilo de gestión en seguridad de los equipos gerenciales en las empresas mineras, y se desarrolle un manejo adecuado y responsable entre el área gestión humana y cultura organizacional. En ese sentido, la excelencia de gestión en seguridad radica en que el elemento humano se conecte de forma sistemática a las estrategías que la organización plantee.

Sep 12, 2005

By A. L. D. Skury

In the synthesis of diamond, the precursor graphite must present a degree of crystallinity to assure optimum yield and quality for the transformed crystals. X-ray diffraction, SEM and TEM analyses were carried out to investigate the structural and morphologic transformations produced in natural graphite by high pressure-high temperature treatment. The present study had as its objective to characterize the morphological and structural changes suffered by a natural graphite that was subjected to high pressure and high temperature treatments in the region of diamond thermodynamic stability. The results indicate that the material that constitutes the gasket, for the deformable capsule, could act as catalyst in the graphite recrystallization process.

Jan 1, 2006

By M Stewart

Alluvial gold deposits in the area studied are preserved on the valley floor and elevated terraces due to a sequence of glacial/interglacial events during Pleistocene and Recent times. Continued regional uplift has overprinted these events. Prospecting by drilling and bulk sampling has demonstrated a complex alluvial gold resource which is now being mined.

Jan 1, 1989

About 15 per cent of total electricity (400 MkW) was generated by nuclear power plants in the world (2009) and about 36 000 tons of uranium has been mined in uranium mines annually. Radioactive waste material is produced from uranium mines and nuclear power plants. The wastes must be disposed or stored safely for long-term. If they leak and/or move from disposal or storage sites due to air/groundwater flow, then a serious environmental pollution can occur. Hence, multi-layer system has been proposed and employed in order to seal off these radioactive waste materials from biosphere. Basically, bentonite is now used for establishing absorbing and sealing layers in this system. However, the amount of high quality betonite is very limited and in some cases it is hard to be obtained.On the other hand, a great deal of refuse from coal burning plants is produced every year and the amount of it is expected to be higher each year, especially in developing countries. More than half of flyash is utilised and the remaining is disposed at the disposal sites. However, the life of the disposal site is limited and it is diff cult to find a new disposal site. It is requested that the percentage of the utilisation of the flyash be increased in every field.From the above two points of view, a flyash-based barrier layer/cover system is considered in this research and this paper discusses the applicability of flyash as a content of barrier layer/cover material based on the results of a series of laboratory tests.

Dec 6, 2010

By R. Todd Swinderman

"Higher production demands across all bulk handling segments require increased efficiency at the lowest cost of operation, in the safest and most effective manner possible. As conveyor systems become wider, faster and longer, more energy output and more controlled throughput will be needed. Add an increasingly stringent regulatory environment and cost-conscious plant managers must closely review which new equipment and design options align with their long-term goals for the best return on investment (ROI).There are primarily two separate market segments using conveyor belts. One is in process industries such as food, chemicals, paper and powders. Handled in relatively low volumes, the bulk materials that enter these processes are generally of a consistent size and quality. The other market includes mining, coal handling and cement, where the bulk material’s quality and size vary, and the volumes are typically much greater. While both segments face similar issues with safety and environmental control, the properties of the materials handled and the volumes transferred suggest different approaches, with one thing in common: increased belt speeds requiring modern equipment upgrades.Safety at higher belt speedsWith companies recognizing that safety does indeed pay, safety is likely to become a new source of cost reduction. The percentage of mines and processing facilities with a robust safety culture are likely to increase over the next 30 years to the point where it is the norm, not the exception. In most cases, with only a marginal adjustment to the belt speed, operators quickly discover unanticipated problems in existing equipment and workplace safety. These problems are commonly indicated by the larger volume of spillage, increased dust emissions, belt misalignment and more frequent equipment wear or failures."

Jan 11, 2018

By Edwards A. B

A table concentrate obtained experimentally by the New Occidental Gold Mines N.L. has unusual interest on account of the presence in it of abundant coated or "black" gold. The concentrate was obtained from ore from the New Cobar mine, Cobar, New South Wales, by feeding the oversize product from a "Dorr Bowl classifier to a Card table.Its assay value was 129 oz. of gold and 52 oz. of silver per ton, yet practically no free gold could be seen on panning.When, however, the concentrate was digested in hydrochloric acid fine rusty gold could be obtained by panning.The following chemical analysis was carried out by the mining company on a similar sample of concentrate.

Jan 1, 1941

By D. Bois, P. Keating, J. Lemieux, M. A. Vallée, M. Allard, R. S. Smith, L. Z. Cheng, M. Chouteau, K. Fountain

"A comparison of data from INPUT, GEOTEM, and MEGATEM airborne electromagnetic (AEM) systems over the Aldermac deposit, Québec, Canada, was undertaken to evaluate the relative ef¬ficiency of these systems for the detection of small, deep conductors. The Aldermac orebody was mined between 1933 and 1934 to a depth of 200 m. A deeper mineralized zone was discovered in 1987. The MEGATEMII system was used to acquire 90- and 30-Hz data over the deposit in 2003 as part of a research project. These MEGATEMII data were compared with data acquired by other AEM systems (GEOTEM and INPUT), and the results show that the MEGATEMII response is ten times larger than the other sys¬tems. For the dB/dt response, 30 Hz gives a better signal-to-noise ratio, whereas 90 Hz has a better signal-to-noise ratio on the B-field.The data were evaluated by numerical modeling. The deposit was best represented by a complex mod¬el, comprising two weakly conductive bodies to approximate the alteration halo, two deeper prisms repre¬senting known orebodies, and three bodies ranging in thickness from 3 to 6 m and in resistivity from 12 to 20 ohm·m, representing the chargeable overburden. This implies that the MEGATEMII system is able to see a small conductive body at more than 200 m depth in an area where the response is contaminated by conductive overburden."

Jan 1, 2009

By George F. Becker

(San Francisco Meeting, October, 1911.) A MERE record of Emmons's professional career would very inadequately represent the man. That he was eminent we know, and our successors will realize in due time; but they must depend upon us for knowledge of a singularly wholesome, modest, unselfish personality, and of a character that did honor to a profession in which trustworthiness is indispensable: Those members of the Institute who met Emmons are his friends, and I never knew one of these who was not the better for that friendship. Emmons was born in Boston, Mar. 29, 1841, the son- of Nathaniel H. and Elizabeth (Wales) Emmons, and was named Samuel Franklin after an ancestor who was of the same family as Benjamin Franklin. He took the degree of Bachelor of Arts at Harvard in 1861, and soon afterwards went abroad to complete his education. From 1862 to 1864 he attended the courses at the École Impériale des Mines at Paris, lie e Beaumont and Daubrée being among his professors. The year 1864-1865 he spent at Freiberg under Cotta and other famous teachers; after which he spent another year in traveling through Europe. Like many other renowned geologists, he approached his ultimate profession from its economic side, and was thus from the first imbued with a sense of high responsibility in the promulgation of scientific opinions or conclusions. With hypotheses which were interesting merely because. they were ingenious or even plausible, he would have nothing to do. In 1867 he joined the Geological Exploration of the Fortieth Parallel at its organization under Clarence King, serving at first as a volunteer, but soon receiving a regular appointment. This expedition was the first one of purely geological character sent out by the United States Government. As Emmons has shown in his admirable presidential address on " The Geology of Government Explorations," its work was founded on a com-

Sep 1, 1911

By D Caley

During the response to the Moura No 4 disaster, use was made of the New South Wales Mines Rescue Service’s ‘Mineshield’ inertisation equipment. The equipment had to be transported from Newcastle, approximately 1400 kms, and the liquid nitrogen a similar distance. The time taken, and therefore availability of the liquid nitrogen, became a significant problem. Operational issues were also experienced during use. Typically the liquid nitrogen is converted to a gas (vaporised) before being injected into the mine. However, as the propane gas tanker used for the vapourising unit was delayed, an attempt was made to inject the liquid nitrogen directly down uncased boreholes. This proved unsuccessful.Following the Moura No 4 disaster and the Moura No 2 disaster, recommendations were made relating to having inertisation capacity for the Queensland coal mining industry. Today the Queensland industry has multiple options available for inertisation, including the high-volume GAG and smaller volume units such as boilers and membrane separation units. Although it ultimately aided re-entry into Moura No 4, most likely due to the issues associated with supply to Central Queensland, liquid nitrogen has not found favour within the Queensland industry as an inertisation tool.Coregas has commissioned an air separation plant in Mackay, improving the availability of liquid nitrogen to Central Queensland. Based on the availability of this nitrogen, recent sealing operations at Kestrel have trialled using liquid nitrogen and associated vapourising units. This paper details the practical application and findings of using liquid nitrogen during routine longwall panel sealing.CITATION:Caley, D, 2017. Using liquid nitrogen for the inertisation of goafs, in Proceedings Australian Mine Vent Conference 2017, pp 35–40 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017