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Use this month wisely — go online and take advantage of your new member benefit. As an SME member, you can read and download for free all of the full-text papers of the Mining, Metallurgy & Exploration (MME) journal, including the 22 papers in the launch Special Issue on Mineral and Metallurgical Processing in Honor of Professor Emeritus Douglas W. Fuerstenau as well as the archived articles of Minerals & Metallurgical Processing (MMP), all the way back to Vol. 1, No. 1. Just follow the instructions on this page.

Collaboration between education providers is the key to long-term sustainability and improved quality in mining education. The mining industry is now, more than ever, an industry doing business on a global basis. Staff are recruited by global mining companies in many different countries and can find themselves deployed anywhere in the world. The mining engineer of tomorrow must be willing to take on this international challenge, and must be educated to a level where he or she has a comprehensive grounding in technical aspects of mining engineering, but also a well-founded appreciation of management, social, environmental and cultural issues which may be encountered around the world. In order to deliver such an education, academic providers must collaborate at both a national and international level. This paper provides an overview of progress that has been made in Australia through the national joint venture ? Mining Education Australia (MEA). Supported by the mining industry in Australia, through the Minerals Council of Australia (MCA), MEA has now been operational since 2007 and is seeing the development of a range of innovative courses and delivery methods, together with a high level of staff co-operation across the country. MEA has also now commenced some international teaching initiatives which are seen as a catalyst for a far greater degree of international collaboration in the future. Such activity is not only to the benefit of the students who are taught by experts from around the world, but it also ensures that individual university programs remain viable in terms of staffing numbers and financial performance. The paper also presents some statistics on recent upward trends in mining engineering student numbers from around the world, in response to the global shortage of mining engineers.

Jan 1, 2009

By Jamie D. McEwan

To cater for the future introduction of 12 car trains, London Blackfriars railway station is being extended from the north end to span across the River Thames. Following the demolition of existing buildings, a number of challenges had to be overcome including working adjacent to a live railway line, above live London Underground tracks and working in small restricted spaces. Trains entering and exiting two lines of track at the bridge's north end of track meant that access was difficult due to the location and proximity to existing infrastructure. The site was very much constrained and congested and there were also a series of works in place to maintain passenger flows so as not to inconvenience the travelling public. The site had been developed many times in the past resulting in a number of obstructions that would require removal during the piling work including old brickwork, reinforced concrete, redundant railway sleepers and track and existing concrete and timber piles. A number of solutions had to be devised to overcome these obstructions. Piling works were undertaken during the day and at night to meet programme.

Jan 1, 2011

By John N. Cunningham

Despite the wide use of micropiles for rehabilitating and retrofitting existing structures, little is known regarding the load-transfer distribution of grouted micropiles in various soil deposits. The rehabilitation of a concrete-frame warehouse in Portland, Oregon, required provisions for the seismic restraint of a new shear wall; the installation of two micropiles was specified to meet project requirements. The micropiles were uncased, 19-m (63-ft) long, 200-mm (8-in) nominal diameter, and reinforced full-length with a 64-mm (No. 20) diameter hardened steel threadbar. Due to space limitations, a sacrificial, instrumented micropile was installed near the two production piles to verify design assumptions. This paper describes the geologic setting of the project within the unsaturated Missoula Flood deposits, instrumentation, load-displacement behavior, load transfer, and Beta-coefficients for the sacrificial micropile.

Jan 1, 2011

By Fred D. Wright, Philip B. Bucky

FOREWORD By E. D. Gardner[$] THE present known petroleum reserves are limited, and unless important new fields are discovered the Nation will be dependent, in the not too distant future, upon imports or upon synthetic liquid fuels to supplement domestic petroleum supplies. As a national defense measure, it would appear desirable to develop a substitute source of liquid fuels within the borders of the country if new discoveries of petroleum should prove disappointing. Congress undoubtedly had this in mind when it passed the Synthetic Liquid Fuels Act (78th Congress, approved April 5, 1944). The act directed the Bureau of Mines to construct and operate demonstration plants for producing synthetic liquid fuels from coal and oil shale, and from forestry and agricultural products. As a part of this program, the Bureau of Mines has built a demonstration plant at Anvil Points, near Rifle, Colo., for retorting the oil shale, and has developed a mine to supply the plant with oil shale. At the beginning of mining operations, the physical qualities of the oil shale, which would have a bearing upon the selection of mining methods and practices for exploiting the deposits, were largely unknown. A comprehensive mining-research program has been set up to determine the best methods and practices to follow to obtain the lowest overall practicable mining cost for producing the oil shale on a large scale. Unusually low mining costs will be necessary for shale oil to be produced commercially. Consideration now is being given to exploiting a series of flat-lying beds 70 ft thick by a room-and-pillar method of three benches with the advance heading at the top. This report is one of a series giving the results obtained in research on mining problems. INTRODUCTION The structure and physical qualities of the oil shale indicate that the 70-ft interval of the oil-shale measure can be safely mined in open stopes; studies indicate that this method would be the most economical one to use.1 As labor will be a major item of expense, the largest equipment that could be operated efficiently in the workings would be required to obtain the lowest practicable mining cost. It was therefore desirable to know the maximum safe span of unsupported rooms and the size of pillars necessary to support the overburden. This paper describes the work done at the Columbia School of Mines Barodynamic Laboratory in determining the maximum safe unsupported roof spans and the minimum safe pillar dimensions for the oil-shale mine at Rifle, Colo.

Jan 1, 1947

Mine wide, underground wireless communications are possible with the use of Ultra Low Frequency (ULF) technology. Due to the propagation through rock of ULF radio signals a relatively small antenna can provide communications coverage over a complete mining operation. Starting as a Personal Emergency Device (PED) for emergency messaging to miners under all circumstances, the ULF communications system has grown to include capabilities of remote control of underground equipment such as pumps and fans and centralised blasting initiation. This technology is now in use on 5 continents having lately made it onto the African mining scene. The paper and presentation will provide the audience with the benefit from international mining know-how in this technology as well as local African experiences. A recent commissioning exercise for example, is expected to pay for itself in electricity savings within a few months. These and other results from practical demonstrations and usage will be covered. This novel technology becomes an integral part of the daily operating infrastructure of a mine with immediate safety and business benefits. It is able to reduce capital expenditure and is designed for ease of routine operational use. The paper will conclude with insights into current R&D for further development of this technology.

Jan 1, 2007

By J. W. Howland

A demonstration of dozer blades, designed for recontouring area-mined spoil and shown effective at Kansas and East Texas surface mine sites, was conducted at a Northeast Arizona surface coal mine to determine their effectiveness in different climate and soil conditions. The specialized tools were: 48-ft angle blade (on side-by-side tractor), 24-ft grading bar, modified 24-ft "U" blade (on side-by-side tractor), and a 13-ft deep "U" blade. Interest in the increased dirt-handling capacity of a previously built 22-ft blade, resulted in the design of a new Centerflow Blade of good versatility, able to maintain increased flow in otherwise difficult-to-move spoil. The demonstration involved 263 acres and showed a reduction of 50% in reclamation costs and 20% in fuel requirements for this mine site over conventional equipment. This savings resulted from improved technology, trained operators, and rigorous application of supervisory and monitoring techniques. Procedures and results of the demonstration are presented and analyzed here, along with guidelines for application of findings.

Jan 1, 1982

By R. R. Sayers

"The number of investigations reported during the past year indicates that control of the health hazard due to abnormal air conditions is still a matter of serious consideration in the mining, metallurgical, and allied industries.Australia. - In an investigation into the health and working conditions of employees in the mining industry of Tasmania and Victoria3, it was found that although pulmonary tuberculosis may occur early in life, silicosis is e disease of slow evolution and does not appear frequently under the ace of 40. A period of at least ten years in the industry was found necessary to produce silicosis, and in no case was the disease found in those who had not worked underground. A very high incidence of silicosis was found in all fields among those who had worked underground 20 years and longer. There was some evidence that silicosis complicated by tuberculosis may occur earlier than uncomplicated silicosis.England. - In a paper presented before the Section on Occupational Diseases of the British Medical Association, Dr. E. L. Middleton, the medical inspector of factories, called attention4 to the occurrence of silicosis in various industries throughout the country.punitive on some quite harmless industries. Thus Middleton says: ""Where the amount of dust is small the action of the phagocytes is likely to be effective, but where it is great . . ."" What dosage is indicated by ""small"" and ""great"" in this connexion? If the meaning of ""small"" were known, would it be correct to go on to say, as he does, ""each successive dose of silica produces a summation of effects""? Then, again, would it be fair to say ""a comparatively brief period of exposure may be the only determining factor""? What, in minutes, hours, or days per week, per month,' or year, is intended by ""a comparatively brief period""? ""Intermittency of the process"" is another expression used in summing up the reasons for and against a standardization of air purity by a gravimetric process or enumeration of the particles; the arguments against such a standardization are, by Middleton, considered strong, but they are by no means convincing to us. A standard has been accepted in respect of the amount of lead in milligrams per 10 cubic metres of air; Dr. Ronald Lane showed in another paper read that adherence to this makes the occurrence of poisoning highly improbable. Mavrogordato has placed on record figures of silica dust at different stages of the improvements in the workings of the Rand mines, and such a control is in constant operation in them today.We emphasize these points because apparently the Government has taken the unusual course of legislating first and postponing inquiry to a later date, as in the ""Various Industries (Silicosis) Scheme, 1939."" The insurance companies also have a considerable interest in the matter of compensation for the silicosis risk. Where exposure - as in the refractories industries, the grinding industries, sandstone industry, and pottery industry - is day in and day out, they rightly demand a premium far higher than for any other disease scheduled under the Workmen's Compensation Act - 5 per cent on the wages bill. row every industrial employer, such as the paint and varnish manufacturer, who has a sack of crushed silica in his store .room, from which he extracts once a week enough to make a paste With spirit and add to his other ingredients in order to give them the necessary ""bite,"" becomes involved, and may have to abandon the use of the material or pay 8 per cent on his wages bill for an absolutely negligible risk.. For meting out justice standardization seems urgently called for."

Feb 1, 1930

By A. K. Anyimadu

Ongoing development work on ultra-fine grinding for various applications at the Group?s concentrators has been conducted by Anglo Platinum over the last few years. Current potential applications for mainstream grinding and concentrate grinding are the subject of a group-wide research and development programme. The first 10 000-litre 2.6 MW IsaMill was jointly developed by Anglo Platinum, Xstrata Technology and Netszch for installation at the Western Limb Tailings Re-treatment project in Rustenburg, South Africa. The unit was commissioned in late 2003/early 2004, and has operated in an intermediate concentrate regrind application successfully since. This paper describes the operational performance to date, as compared with the original duty specifications and objectives. The first mainstream M10 000 IsaMill with a 3 MW drive will be operational in November 2006 at the Potgietersrus Platinum (PPL)?Platreef? Sandsloot Concentrator in South Africa?s Limpopo Province. Keywords: Western Limb Tailings Re-treatment Plant, IsaMilling, Platreef, platinum, palladium, PGMs, tailings.

Jan 1, 2007

By A. W. Bester

Paper written on project work carried out in partial fulfilment of B. Eng. (Mining Eng.) Cullinan Diamond Mine currently handles 3.2 million tons of run of ore per annum. This is done by means of an underground train system, which is located at 763 metre level. Four trains, one in each quarter of the pipe, collect ore from passes and transport it to centrally located tips in the north and south of the pipe. The ore is then split into coarse and fine fractions. The coarse fraction proceeds to the primary crushers in the north and south. Historically, mining has been performed in such a manner that an equal amount of ore has reported to each quarter of the pipe. However, the tonnage profile of the mine will change such that the ore will no longer be split equally. For approximately five years the majority of ore will report to the east and thereafter most of the ore will report to the western portion of the mine. This will continue for the remainder of the current infrastructure level?s operational life. Coupled with this is the fact that the mine is aiming to increase its annual production to 3.8 million tons. The result is that the current ground handling system cannot accommodate the additional tons and therefore alternative ground handling options have been investigated. The continued existence of Cullinan Diamond Mine relies on finding a system that can economically handle the additional tonnage. Three options were investigated. Firstly, a train option, which would be an upgrade of the current system, was investigated. Two truck options were also investigated, the first of which was a conventional truck option. The second truck option was more interesting and involved an unfamiliar Combi truck system. The truck options were investigated primarily due to the fact that the block height of the BA West (a new production block) can be increased by 15 meters if a truck option is decided upon. This would create a significant increase in revenue for the BA West project. Each of the options was assessed in terms of its physical and financial feasibility. In terms of the physical constraints, it was found that all three systems could work. Detailed financial analysis indicated that either of the two truck options would be a suitable solution. However, due to the limited information regarding the Combi truck option, it should be further investigated. This applies particularly to the actual running and maintenance costs for the equipment.

Jan 1, 2005

Titanium and Zirconium Industries Pty. Ltd. separates rutile and zircon from heavy mineral concentrate recovered from sand dunes on the east coast of North Stradbroke Island, Queensland. Separation plant feed is delivered to Dunwich, on the west coast, by a seven mile aerial ropeway traversing the island. Mining and concentration is effected by two floating dredge-concentrators now operating on the beach 31; miles from the aerial ropeway terminal. Heavy mineral concentrate is transported hydraulically from the dredges to the ropeway through a 6 in. pipeline. Six pumps in series deliver 24 ton/hr of dry solids in a pulp containing 13 per cent solids. For maximum economy the transfer pumping system is controlled deliberately to cause transportation in the zone of incipient settlement of solids, ieat velocities below the limit deposit velocity for the particular pipe diameter, pulp density, and specific gravity of solids. Automatic density control, based on a combination of power consumption and pipeline pressure, eliminates the danger of plugging the line but periodic flushing is necessary to remove gradual accumulation of solids in the bottom of the pipe. After 15 months operation the pipeline was descaled with hydrochloric acid to remove severe blistering with rust nodules, regrowth of which is now prevented by continuous injection of inhibitors. After transporting 100,000 tons of heavy mineral the average wear on the steel portion of the pipeline was 0·01 in. and indications are that wear on the asbestos cement portion is less.DESCRIPTION OF OPERATIONSGeographyTitanium & Zirconium Industries Pty. Ltd. (T.A.Z.I.) operates on North Stradbroke Island, some 30 miles southeast of Brisbane, Queensland. The island is approximately 25 miles long and eight miles wide, and is bounded on the east by the Pacific Ocean and on the west by Moreton Bay (Fig. 1). With the exception of a small outcrop of volcanic 1. Manuscript received at The Institute. 8th May. 1962. This paper was presented at the Annual Conference of The Institute. 5th-11th August. 1962.

Jan 1, 1962

The Mineral Sector Development Project, sponsored by the World Bank, has been set up to revise the legal, regulatory and fiscal framework for the minerals industry in Tanzania, with a view to attracting mining companies and investors to the country and facilitating future minerals development. One component of this project, the Environmental Management Framework for the Mineral Sector, was awarded to Wardell Armstrong of the UK and ENV Consult of Tanzania. In developing a new framework of environmental regulations, emphasis was placed on developing realistic standards which reflect local conditions and prevailing values. The main corner-stones of this approach are; effective environmental impact assessment procedures; establishment of environmental management procedures; and monitoring and auditing of companies? performance. The favoured approach involves a three-tier framework, as follows: ?Framework environmental provisions within the new Mining Act; ?Regulations covering more detailed environmental requirements ?Guidelines and/or Codes of Practice, which may in future become regulations in their own right. Careful consideration has been given, in developing the framework, to the limited resources likely to be available for implementation to the Ministry of Energy and Minerals and this has influenced the approach that has been adopted. This paper outlines the main components of the environmental management framework and discusses some of the important issues raised by these proposals.

Jan 1, 1998

By L. F. Ruppert, P. A. Freeman, R. C. Milici, S. J. Tewalt, L. J. Bragg

The U.S. Geological Survey has completed a dig-ital coal resource assessment of six of the top-producing coal beds and coal zones in the northern and central Appalachian Basin coal regions. These include the Pennsylvanian-aged Pittsburgh, Upper Freeport, Lower Kittanning, Fire Clay, Pond Creek, and Pocahontas No. 3 coal beds and coal zones. Resources were calculated on all of the coalbeds/zones, with the exception of the Lower Kittanning coal bed. Preliminary original resources are estimated at about 93 billion short tons (84 billion tonnes), of which about 66 billion short tons (60billion tonnes) remain. Much of the remaining coal in all five coal beds/zones is thinner [<3.5 ft (1.07m)] and deeper [>1,000 ft (305 m)] than the coal that has been mined, but economic resources are still available and mining in each coal bed/zones will continue throughout this decade and into the next given current market conditions.

Jan 1, 2001

By Stone. Jon P.

INTRODUCTION Countries that are currently developing their mineral potential have unique information systems requirements to support these activities. The mining laws usually grant the State considerable authority over the process. In many instances, the mining laws give a government agency the responsibility for granting and controlling exploration permits and development concessions. This is the case in Costa Rica. The Direcion of Geologia, Minas, y Hidrocarburos (DGMH) of the Ministerio de Industria, Energia y Minas (MIEM) is responsible for the management and operation of the National Mining Register. This paper describes the results of two studies of the information system requirements to support the National Mining Registry as well as those supporting some of the other function of the DGMH. The first of the studies reviewed the situation before the installation of computer equipment. The second study evaluated the installed systems. BACKGROUND Historical Perspective Mining in Costa Rica is at present a relatively minor part of the economy. It consists primarily of industrial minerals and gold production. Gold production is largely by small-scale miners and may be more substantial than reported. There is considerable interest on the part of the Government in both having a better understanding of the existing mining industry and promoting future development. Mining law was first provided by the Ordinanza de Mineral (of 1830). This was replaced by the first Mining Code of 1953. Apparently, one of the first problems caused by the 1953 law was the granting of concessions which were not worked. A 1968 agreement with ALCOA also resulted in political conflict. The Government worked on a new Mining Code for many years and in 1982 the current Mining Code was enacted. Draft implementing regulations were prepared in April 1984. Mining Code of 1982 The Mining Code of 1982 addresses most aspects of mining in Costa Rica including the declaration that all mineral resources are to be the property of the State. The State may grant exploration permits and exploitation permits. The exploitation of hydrocarbons, radioactive minerals and certain water resources was reserved to the state. The DGMH was given authority to settle placer claim disputes, maintain a registry of exploration permits, and exploitation concessions. and generally supervise mining activity. Towards this, the Mining Code of 1982 includes rather detailed requirements for the processing of application for permits and concessions. Mining Code Application Requirements The following briefly describes the requirements to give the reader a feeling for the complexity of the process. Currently, over 1,000 active applications, exploration permits and exploitation concessions are being monitored under the process. The number remains relatively consistent in that the number of new applications is usually about the same as the applications that are put aside. The time and date of the filing must be certified by the DGMH. The application must include all the information specified in the Mining Code. If incomplete, DGMH must notify the applicant of the deficiencies or omissions and direct that the applicant correct the deficiencies or omissions within 8 business days (a single 30 business-day extension is allowable). If the applicant does not respond as directed, the application is deemed as not having been filed and the pertinent information is placed in the files. The DGMH must reject the application outright and direct it be placed in the files in the following cases: (a). If the new application covers the area of a previous permit or concession, either being processed or already granted.

Jan 1, 1987

By Matthew Janes

Statnamic load testing is becoming widely accepted as a method to quickly and economically determine the load-deflection behaviour and ultimate static resistance of high capacity deep foundations. Strain instrumented large diameter bored shafts were tested at four locations for the federal and state Departments of Transportation in the United States. Tests were conducted vertically (to 30 MN) and laterally on the shafts and, in some cases, testing was completed over water. Instrumented shaft test results provided shaft load distribution with depth and shaft shear transfer stress throughout the soil stratum. Shaft end bearing and ultimate end bearing stress values were provided. On two projects, Osterberg load cells provided comparative static data for skin friction and end bearing. Correlations between Statnamic derived static load-displacement results and Osterberg load-deflection results are very good. Statnamic lateral load test results were correlated with static lateral results in addition to providing useful dynamic response and damping data.

Jan 1, 1996

By Met M, Worner H. K

In pursuance of the investigation into the influence of various elements on the properties of lead during the past year, the effect of several elements on the creep rate of commercially pure lead has been investigated; a standard initial stress of 500 lb. per sq. in. having been adopted for comparison purposes. Other work which has been carried out indicates that the relative results of creep tests may be altered by varying the applied stress, but this aspect of the problem will need to await further investigations for itscomplete elucidation. The results obtained with dilute tellurium alloys are considered sufficiently interesting, and in some respects are so extraordinary, as to warrant publicatiorr at this stage.n must be realised however that, since the results obtained appear to be at variance with those said to have been obtained in practice and those previously published, the present investigation can only be considered as a contribution to our knowledge of the general problem.Consequently it is not considered advisable or necessary to offer detailed explanation of the results given. In fact, some features of the tests about to be described will need further investigation before an adequate explanation is possible.

Jan 1, 1936

By M. Ayhan

Drums of a modern longwall shearer are manufactured to include various constructional features conveying extracted material onto the face conveyor as efficiently as possible. Designing a drum with a conical shell or with reduced vane length, consequently with a stepper vane angle, is the most widely employed method in an attempt to increase loading efficiency. This study compares loading performances of two such drums, one having a conical shell with modified loading vanes, the other with a cylindrical shell with reduced vane length. Firstly, the loading performances of drums are predicted and the maximum haulage rate attainable with the drums are calculated. Then the performances of drum are compared by long-term comprehensive underground trials with coal shearers under similar conditions during the production operation of Park Termik Cayirhan coalmine in Turkey. Although higher loading performance is predicted for cylindrical drums, the in situ trials point out that Globoid drums have a slightly higher loading performance than cylindrical drums. Furthermore, the relationship between operational variables, i.e. extraction height, sumping depth, haulage rate and in situ loading performance, were investigated statistically on the basis of data gathered during the underground trials. Keywords: longwall mining, shearer drums, loading performance.

Jan 1, 2006

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Jan 1, 2009

By I. Ocak

The modulus of elasticity of rock material (Ei) is an important rock property that is used as an input parameter in the design stage of engineering projects such as dam and tunnel constructions, mining excavations, and so forth. However, determination of the modulus of elasticity is sometimes difficult to obtain by laboratory tests because high-quality cores are required. For this reason, empirical methods for predicting the modulus of elasticity of rock material have been popular research topics in recently published literature. In this study, the relationships between the uniaxial compressive strength (UCS), unit weight (?) and modulus of elasticity for different types of rocks were analysed by using 177 data obtained from laboratory tests carried out on cores obtained from drill holes within the area of the Kadiköy-Kartal Metro line (Istanbul, Turkey). Keywords: Kadikoy?Kartal Metro, uniaxial compressive strength, unit weight, estimating the modulus of elasticity.

Jan 1, 2008

By R. Stenne

This paper deals with a complementary soil investigation which being part of the contract helped understand the behavior of a softened clay and adjusted the design of a retaining structure accordingly. The investigated softened clay proved to have lost its original strength but had maintained some characteristics of its stress history and in particular high horizontal stress. Pressuremeter tests and flat dilatometer tests were of interest to estimate the at rest earth pressure. A design consisting of a T-shaped slurry wall in conjunction with transverse walls was the most effective solution to cope with high active pressures and low passive pressures.

Jan 1, 2000