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By A. F. Roberts

The subject of mine fires is a very wide one. To give reasonable coherency, the paper concentrates on the behaviour of fires in the ventilated airways of mines; spontaneous combustions are not considered. The following topics are considered in some detail: 1) Material selection: Performance requirements for mining materials in terms of flammability and smoke/fume production; methods of test and need for relevance to mining conditions. 2) Fire growth: The influence of material properties and method of use on the rate of growth of fire in a mine roadway; the influence of ventilation, slope, material orientation, proximity of walls and roof on fire behaviour. 3) The fire in the ventilation network: The influence of fire on the ventilation distribution; the circulation of fire products in the network. The influences of these topics in determining fire control strategy are then considered but topics such as fire detection and fire extinction methods are not reviewed in detail. An extensive Bibliography on papers relating to mine fires is included.

Jan 1, 1989

By R. Frank Chiappetta

A new blasting technique has been developed by International Technologies, LLC. to eliminate subgrade drilling, lower ground vibrations, improve fragmentation and reduce explosive consumption. The new technique utilizes a uniquely designed borehole plug, with a bottom hole air deck and a predetermined stemming mass on top of the plug. This combination is referred to as the Power Deck?. Single holes and full scale tests were conducted by Blasting Analysis International, Inc. (BAI) to determine how the system works, the mechanisms behind its success and the best design parameters to use for the given rock conditions. Results have shown reduced or eliminated subgrade drilling, ground vibration reductions of up to 33%, reduced explosive consumption by 16 to 25%, and improved fragmentation by up to 25%. This paper summarizes the methodology, field test setups, analyzes procedures and results for one series of single hole and full-scale tests which were performed in a Pennsylvania, USA quarry.

Jan 1, 2004

By William C. Cooley

SUMMARY A review is presented of the state of development of high pressure water jet equipment and of large impact hammers for rock tunneling. Information from the U.S.S.R. is based on published literature and three personal visits. Applicable papers which were presented at the International Symposium on Jet Cutting Technology in Coventry, England in April 1972 are reviewed. Data are presented on continuous jet systems, pulsed water cannons, and hydraulic-powered impact hammers with respect to the specific energy of rock breakage and potential application in tunneling machines. INTRODUCTION It has been estimated that the cost of underground excavation during the period 1970-1979 in 15 countries of the Organization for Economic Cooperation and Development will be over $54 billion, an increase of 104% over the period 1960-1969. It is expected that 55% of the tunneling construction will occur in hard rock (Ref. 1). Present tunneling machines are generally limited to soft and medium-hard rock. When used in hard rock, the cost of replacing mechanical cutter bits is high. Therefore there is a need for improved rock fracture methods which can be applied economically in tunneling machines for hard rock. Water jets and mechanical hammers are two

Jan 1, 1997

The ready solubility of gold in dilute aqueous solutions of the cyanides of the alkalies or alkaline earths provides a convenient method for the separation of the precious metal -from the large surplus of associated materia1. The finely ground ore is pulped with a weak solution of cyanide, agitated to dissolve the gold, filtered and washed. The lowgrade filtrate is then clarified and the gold precipitated by some electronegative agent, the most usual being finely divided zinc or zinc dust. The slight precipitate is collectedon some form of filter coated with a filter aid, the filter cake being then known as "gold slime".A typical analysis of this slime is given in Table 1.

Jan 1, 1956

By Douglas W. Fuerstenau, Pradip Pradip

The design and development of selective flotation collectors has been the key to the remarkable success of flotation in beneficiating complex, difficult-to-process ores. Sustained research efforts in the field over the past hundred years have led to delineating the scientific basis of selective mineral flotation in terms of the crystal chemistry and the surface and colloid chemistry of minerals including their solubility, and the aqueous solution chemistry of added reagents. It is now well-established that the electrical double layer theory (EDL) is the most powerful means of quantifying the relative strength of mineral-reagent interactions in the case of nonsulfide minerals. We illustrate the utility and the power of the EDL in delineating the science underlying selective mineral flotation with the help of a few examples taken from our own work, in particular on the selective flotation of rare-earth minerals (bastnaesite) from associated semisoluble minerals (barite and calcite) using alkyl hydroxamate collectors and the flotation separation of lithium-containing minerals (spodumene) from associated alumino-silicate minerals with oleate (fatty acids). Both of these mineral separation systems are of contemporary research interest and of immense value to the industry today. Recent advances in utilizing molecular modeling computations, particularly in the context of quantifying the effect of crystal chemistry and the relative distribution of adsorption sites available on mineral cleavage planes, are also reviewed.

By C. K. Eilerts

Knowledge of the phase relations of the fluids that exist in the porous spaces of rocks constituting natural petroleum reservoirs and of the behavior of these fluids under various field conditions of operation is essential to the conservation of petroleum and natural gas and to their efficient recovery. The problem of determining whether these fluids are in the liquid or gaseous state and of recognizing the transitions that may take place as the material in the reservoir is subjected to different conditions of pressure and temperature confronts many producers today, especially in certain fields. The subject has grown rapidly in importance since the discovery of and production from deeper reservoirs that have correspondingly higher pressures and temperatures as compared with shallower

Jan 1, 1938

The 107th Annual General Meeting of The South African Institute of Mining and Metallurgy was held at The Country Club, Johannesburg, Napier Road, Auckland Park on Wednesday, 11 August, 2004. Welcome The President extended a special welcome to the guests and representatives of our sister institutes and other associations, also to recipients of awards, senior members of industry, Honorary Life Fellows, past-presidents, our members and other guests, among them the following: Ralph Bagirathi, Executive Member, African Mining Association Rudi Rudolph, President, Association of Mine Managers of South Africa Andrew Whibley, President, Association of Mine Resident Engineers of South Africa Dr Con Fauconnier, President, Chamber of Mines of South Africa Nxolisi Diliza, Chief Executive Officer, Chamber of Mines of South Africa

Jan 1, 2004

By Albert Ladd Colby

A GLANCE through the Bibliography appended to this paper will show that the Transactions of this Institute contain what virtually contitutes a history of the development of the manu¬facture of steel rails in this country and abroad. It is, therefore, fitting that this paper, bringing one branch of this important subject down to date, should be here presented, and it is also appropriate to select this joint meeting of our Society with the Iron and Steel Institute to compare the specifications covering the rails produced in these two countries, and to propose a standard specification to govern the manufacture of American rails for export. During the last ten years the production of Bessemer steel rails in the United States and Great Britain has amounted to 32,128,720 gross tons. Nearly 19,000,000 tons have been rolled in the past five years. The next five years will see an even larger output, owing partly to the extension of railway projects in the Orient, in South and Central America, in Mexico, and in Australia and the other British Colonies. Of late years, the American rail-mills have so largely increased their daily output, that trade conditions have often made possible the delivery of American rails to foreign ports. The tenders submitted by American mills, however, have always been accompanied by requests for changes in the foreign specifications, chiefly in the reduction of the amount of testing required; and it has only been natural, especially at first, that the engineer, whose specification had always been accepted without question by British mills, should interpret American tenders 'as an evidence that an inferior rail would be furnished

Sep 1, 1906

By Allan E. Koski

Ceveland-Cliffs uses a specialized software package in mine planning at the Empire Mine, an iron ore mine it manages on Michigan’s Marquette Iron Range. The application puts together years of mining experience that began in the early 1960s on the eastern end of the Marquette Range. The Empire Mine is in its 38th year of production. It uses the software to model a complex and highly variable low-grade magnetite ore body, capturing the economics of mining and processing to the final product. With special attention given to geostatistical methods, the software is used for all geologic modeling, ore reserve estimation, ore control, pit design and short- and long-range planning.

Jan 1, 2000

By Patterson B. G

The small party of mining men who formed the original Mount Morgan Syndicate in 1882, commenced operations on the top of the mountain with what were practically nothing more than small hillside quarries, It was not until 1891 that underground stoping began, and open-cut mining therefore commenced with the commencement of operations. This hillside quarrying, however, seems to have been quite haphazard and unsystematic ; there is no trace or sign of any properly devised mining scheme. This can be seen plainly enough from an examination of old mine plans; for in less than five years after stoping was; adopted, the open-cut was down into the stoped-out ground. The following table, prepared from these old plans, shows the downward trend of the excavation in the past fiftyseven years:-

Jan 1, 1939

By Nicholas P. Callas

This report presents research results obtained in the investigation of deviation control of boreholes in the rotary drilling process. The approach taken in this research is the passive method of placing stabilizers in the bottom-hole assembly to control deviation. Extensive use was made of the drill string mechanics theories of Lubinski and Woods. Analog, digital and hybrid solutions to variety of boundary value problems were investigated in order to determine the best models for bottom-hole assemblies. Field drilling data was analyzed and the results obtained from various models were compared to the actual drilling results. Various accomplishments of this work have been published in open energy industry literature, with more publications to follow.

Jan 1, 1981

By C Thompson, D Connelly

The history of mill liners has evolved over time and this paper tracks the changes and development of liner technology. It provides an overview of the primary types of liners, the design and the materials of construction. The design of a mill liner is driven by application, materials of construction, casting technology and handling issues. The choice of solid steel, grid liners, rubber or composites and magnetic liners is based on many factors.The methods used for monitoring wear and predicting eventual change out time are many and varied. The contribution of discrete element modeling (DEM) analysis in predicting wear profile is discussed.Mill trajectory and DEM software programs are used with great effect to predict the effect of lifter height, face angle, high low lifters or mill speed. In the field, trial and operational experience is used or improvements/design concepts at one operation are applied to another. Broken mill lifters, accentuated wear and other problems can be better understood using hardness testing, chemical analysis and photo micrograph analysis of pearlitic or martensitic structure along with fracture face observations. This forms a part of the typical root cause analysis. However given correct and sound liner and lifter, feed and discharge design media selection, and materials of construction, the majority of premature liner or bolting failure is normally attributed to incorrect operational methods such as excessive high ball to feed ratio, incorrect mill speed relating to lifter ball throw, incorrect media selection, "tramp" material entering the mill charge from upstream or recirculating process and understanding the specific mill operation in question.It is hoped that this paper will benefit mill operators who are faced with challenges of improving wear life and at the same time optimizing mill throughput and performance.CITATION:Connelly, D and Thompson, C, 2013. The selection design and application of mill liners for large wet grinding mills, in Proceedings MetPlant 2013 , pp 133-140 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 15, 2013

1. Domestic Production and Use: In 1974 twelve companies operated 31 primary aluminum reduction plants, three firms accounting for 64% of production. Washington, Oregon, and Montana accounted for 32% of the total production; Gulf Coast States, 24%; Northern States, 33%, and other Southern States 11%. Output of primary metal in 1974 was valued at $3.4 billion. About 80% of the secondary recovery was from new aluminum base scrap and 20% was from old scrap. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1974, building accounted for about 27%; transportation 19%; electrical, 13%; packaging, 15%; and consumer durab1es, 9%.

Jan 1, 1975

By C. R. Tinsley

Investment activity in the Pacific Rim of Fire has seen a phenomenal surge from epithermal gold exploration. Individual countries are attractive because of lower up-front minerals lease costs (US, Canada), better geological prospectivity (Chile, Indonesia), or cheaper equities (Australia). Since the October 1987 stock-market crash, large companies are shedding minority joint venture interests to focus on core businesses. Some vertical integration is evident in Japanese coal investments in the Pacific Rim. This paper does not cover the aluminum industry oligopoly which is multi-national in character nor does it cover the many Canada to US minerals investments. It will be interesting to see if the new US-Canadian free-trade treaty will reverse that investment flow.

Jan 1, 1990

By Marlion T. McQuinn

This paper will discuss the design, construction, and performance of the support of excavation on the Dulles East and West Automated People Mover Tunnels and Station projects. The elements of the system included drilled soil nails and rock anchors with reinforced shotcrete to the excavated face. We will discuss the geotechnical characteristics, design and construction considerations, loading criteria, construction techniques, schedule constraints, and performance of the support of excavation system. In consideration of the conference theme, there will be a discussion of the application of the real-time instrumentation monitoring program. The project team worked to design and install approximately 710,000 square feet of shotcrete and 19,000 soil nails/rock anchors as well as excavate over 720,000 cubic yards of rock materials within 15 months and in such a manner as to minimize the disruption to airport passengers and operations.

Jan 1, 2006

By Elliott A, Kingsnorth D. J

The development of a large high grade spodumene orebody, in excess of 30M tonnes containing at least 7M tonnes at 4.0% Li20, by Lithium Australia Ltd at Greenbushes, Western Australia is significantly increasing the world consumption of lithium minerals. The availability of two low cost sources of lithium, spodumene concentrates (7.5% Li20) and glass grade spodumene (4.8% Li20) has been welcomed by the ceramic and glass industries as it assists them to lower their raw material costs at a time when they are facing severe competition from alternative materials. While there is no shortage of lithium reserves in the world, there has been a shortage of high quality lithium minerals. The Lithium Australia development has filled this need. The favourable factors of high grade, low impurities, open cut mining and existing infrastructure make this an ideal low cost source for a long term downstream lithium industry. The Lithium Australia mine development has filled the need for a reliable long term supply of lithium minerals. The long term viability of this resource is ensured by the unique combination of the following key attributes of the development : High grade reserves of 7.OM tonnes of 4.0% Li20 within 130 metres of the surface, contained within a total proven reserve of 30M tonnes of 2.8 % Li20. Open pit mining with stripping ratio of less than 2.5:1 waste:ore. Low impurities levels, particularly in those elements, that have a detrimental effect on the colour of glass/ceramics i.e. iron, manganese, titanium and chromium. An existing mine infrastructure that includes an adequate water supply for all foreseeable processing requirements. A sophisticated spodumene concentrator utilizing statistical process control to produce a consistently high grade product with minimal impurities. A technically qualified stable workforce fully acquainted with spodumene processing techniques. Greenbushes high grade concentrates have found ready acceptance in the specialty ceramic and glass industries during the past four years. The consistency and high grade/low impurity level of the product has enabled its use in the production of television tubes, oven to table ware, glass fibres, specialty glasses and ceramic glazes.

Jan 1, 1989

By H. F. Zurbrigg

Introdduction The main line of ascent in the development of the nickel industry may be traced back through the International Nickel Company of Canada, Limited, to its earliest antecedents, the Canadian Copper Company and the Orford Copper Company. Mining geology is but one aspect of the overall development of this organization, and the stress it has placed on geology grew according to the need. In the early days, intensive geology was not required because ore supply was not one of the main problems of this or any of the pioneer companies. The difficulty then was to find economic methods for reducing the ores to nickel and copper, and markets for absorbing nickel in the face of a limited demand from consumers heavily prejudiced in favour of the New Caledonia product. "Very early in the history of the region it was patent to everyone that to share in the full benefits of the industry the same individuals or company must control the whole of the operation necessary to manufacture the finished product' (1, p. 45). These conditions were fulfilled for the International Nickel Company in 1902 when the Canadian Copper Company (incorporated 1886), with its ample ore supply, took the initiative to merge its interests with those of the Orford Copper (Refining) Company (incorporated 1887) to form the new company which, with reorganizational changes, emerged as the producer of the overwhelming bulk of the world's nickel. The Mond Nickel Company, Limited, entered the field in 1899 with a refining process, and over a period of years acquired ore through purchase of mining properties. This Company operated successfully and independently until 1929 when its assets were joined with those of the International Nickel Company in order to permit the most economic exploitation of the Frood-Stobie orebody in which both Companies were interested.

Jan 1, 1948

By Henry Kreisinger

Some of the investigations conducted by the Bureau of Mines have for their object the collecting and disseminating of information regarding methods by which the fuels of the country may be most efficiently used. As the analysis of flue gases tends to develop better methods of firing, which in turn reduces waste of fuel, the Bureau of Mines in this bulletin presents for the benefit of those in charge of boiler plants and all other persons interested detailed information on methods of sampling and analyzing flue gases, and on the utilization of the analyses in promoting boiler-room economy. This bulletin is intended to be a companion to Technical Paper 80,a and is written in plain and nontechnical language, as far as possible, so that it may be readily understood by persons who have not had the advantage of a technical education. Whenever possible, illustrations of apparatus and methods of handling have been used rather than elaborate descriptions.

Jan 1, 1915

The Bega granite at Whipstick, N.S.W., consists of a granite metasomatically altered to leucogranites and a spessartite-granite. The ore occurs in pipes controlled by jointing and shows evidence of post-depositional tectonic forces.The principal ore minerals are molybdenite and bismuthinite, with minor amounts of uraninite, pyrite, gold, bismuth, joseite A, joseite B, tetradymite, chalcopyrite, arsenopyrite, and skutterudite. The gangue minerals are microcline, albite, quartz, muscovite, and spessartite, with fluorite, chlorite, magnetite, and biotite as accessory minerals.The intrusion of granite was followed initially by ascending metasomatic fluids which penetrated along joints to be trapped in the domed roof of the intrusion to form the leucocratic granite. Iron-manganese-rich fluids metasomatically altered the granite to a spessartitegranite which is associated with the later deposited ore.Quartz veins and dykes of varying composition post date the ore deposition.

Jan 1, 1968

By André Vien, Pedro Gonzalez, Julio Palomino, Rob Perry

"In many mineral processing plants ore is reclaimed from a stockpile using multiple feeders. The discharge from these feeders is combined onto a single conveyor from which total tonnage is measured. Typically, operators set feeder output ratios to adjust the proportion of total tonnage drawn from each feeder. From a process control perspective, this system is not easy to control because the response time of each feeder depends on the distance from the feeder to the weightometer. This paper proposes a simple and elegant process control strategy to manage feeder ratio changes and the associated long and varying process dead-times. Changes in feeder speed are delayed and filtered to compensate for transport delays between feeders. The strategy was evaluated by simulation and installed on a mill feed system.ResumenEn numerosas plantas procesadoras de minerales, el mineral es extraido desde una pila de almacenamiento usando varios alimentadores. La descarga de estos alimentadores es recibida por zinica correa transportadora, en la cual se mide el tonelaje total. Comzinmente, los operadores colocan un valor determinado en cada controlador de razdn para ajustar la proporcidn del tonelaje total extraido por los alimentadores. Desde el punto de vista del control automatic0 de procesos, este sistema es dijkil de manejar debido a que el tiempo de respuesta de cada alimentador depende de la distancia de este respecto a la ubicacidn del pesdmetro. Este trabajo, propone una estrategia de control, simple y elegante, para compensar los cambios de razdn a cada alimentador y los tiempos muertos del proceso largos y variables. Los cambios en la velocidad de los alimentadores son retardadas y filtradas para compensar los retardos del transporte entre alimentadores. La estrategia fue evaluada por simulacidn, instalada y probada en un sistema de alimentacidn a molino."

Jan 1, 2000