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By A. Deneys

This paper reviews industrial gases used in primary copper production. Copper smelting industrial gas demand has steadily increased since the first commercial oxygenconcentrate smelting in 1952 [1]. In copper production oxygen for smelting is the dominant industrial gas use followed by oxygen for converting. Nitrogen is finding increased use in copper smelters. Nitrogen is used for porous plugs for copper converting and anode refining [2-5]. Nitrogen can be used for concentrate drying [6,7] and is also used in some Ni-Cu smelters as a coolant in Peirce-Smith converting [8,9]. Industrial gas supply options of cryogenic or adsorbent based on-site plant or cryogenic liquid delivery are detailed.

Jan 1, 2007

By H. S. Benson

This report documents, from concept through field testing, the pan scraper Wheel Slip Monitor. The function of this device is to instantly warn the scraper operator of wheel slip and thus enable him to take immediate corrective action. Knowledgeable pan scraper people recognize that the preponderance of scraper tire damage and wear occurs during useless wheel slip when the scraper operator attempts to increase machine draft beyond what traction will allow. The resultant shortened tire life has become very expensive. The Wheel Slip Monitor reported here provides the means for relieving the scraper operator of attempting to judge wheel slip on tires he cannot see. Direct and intuitively understandable audible and flashing light warnings tell the scraper operator which wheel is slipping and also indicate the relative magnitude of the slip. Beside the Wheel Slip Monitor's patent utility as a real time operator aid, it has unique potential for application to extended term wheel slip history acquisition under field conditions. This information has never been easily available and it promises practical value in pan scraper management.

Jan 1, 1983

By Jorge Castillo

This paper presents a dynamic analyses of heap leach pad stability under high phreatic levels and various levels of seismic loading. The dynamic analysis were conducted as fully non-linear two dimensional analyses with fully coupled liquefaction triggering using the Fast Lagrangian Analysis of Continua (FLAC) computer code. Also, the geotechnical parameters, appropriate earthquake record selection and modification, model calibration, numerical analyses and results are discussed.

Sep 12, 2005

By Jon A. Hummer, Aleksandar D. Bugarski, Shawn Vanderslice, Teresa Barone

A study was conducted to examine the potential of diesel emissions control strategies based on retrofitting existing power packages with exhaust aftertreatment devices and repowering with advanced power packages. The retrofit systems, a diesel oxidation catalyst (DOC) and diesel particulate filter (DPF), were evaluated individually using a US EPA tier 2 (ter 2) engine operated under four steady-state conditions and one transient cycle. The DOC effectively curtailed emissions of CO, and to some extent organic carbon (OC), elemental carbon (EC), and aerosol number concentration. The DPF system offered substantially higher reductions in OC and EC mass and aerosol number concentrations. Both, the DOC and DPF achieved reductions in the aforementioned emissions without adversely affecting emissions of NO2 and nano-sized aerosols. The strategy of repowering with an advanced system was examined using a US EPA tier 4 final (tier 4f) engine equipped with a cooled exhaust gas recirculation system and diesel exhaust fluid-based selective catalytic reduction system, but not with a DPF system. The tier 4f engine contributed substantially less than the tier 2 engine to the EC and OC mass, aerosol number, and CO, NO, and NO2 concentrations. The tier 4f engine was very effective in reducing aerosol mass, NO, and NO2 concentrations, but it was not equally effective in reducing aerosol number concentrations. The implementation of viable exhaust after treatment systems and advanced diesel power packages could be instrumental to the underground mining industry to secure a clean, economical, and dependable source of power for mobile equipment.

The Objective: To reduce the noise generated by the exhausting air from a pneumatic roof bolting drill to a maximum of 90 decibels. Any attachment used for this purpose must be lightweight and must not cause a significant increase in back pressure. The Approach: Absorb the noise with a properly designed muffler that will permit sufficient airflow without affecting the normal operation of the drill. How It Works: The air exhausted by the drill enters the muffler through perforated disks into a resonator chamber. It then passes through a series of expansion and contraction chambers and is expelled to the atmosphere through another perforated disk. The basic muffler design for the pneumatic drill was established by using both digital computer analysis and experimentally simulated noise tests. The measured parameters used in the computer program consisted of inlet and outlet pressures, temperatures, airflows and exhaust areas. United

By Oliver C. Fursman

The Bureau of Mines undertook this investigation in order to determine the feasibility of producing commercially acceptable alumina and iron by application of the Pedersen process to high-silica, high-titania, ferruginous bauxites of the Pacific Northwest. Calcium aluminate slags were produced by smelting bauxite with coke and lime in an electric-arc furnace. Over 90 percent of the total alumina can be extracted by sodium carbonate solution from slags of properly controlled ternary-phase composition (CaO-Al203-SiO2) that are cooled slowly enough to permit adequate crystallization of the 2CaO-SiO2 and the calcium aluminate compounds. Most of the iron charged was recovered in the regulus; the slag contained about 2 percent iron (as iron oxide), regardless of smelting time.

Jan 1, 1968

By Antti J. Perala, Teemu J. Yli-Kovero

"Efficient use of land is constantly requiring more underground construction. Minimized execution time and disturbance to surroundings and nearby structures are essential benefits for all construction techniques. To meet the demands of a modern construction project, suppliers have to be able to provide high-quality and tailor-made products just on time. RD pile wall is a retaining wall based on drilled steel pipe piles which are connected to each other with special interlocking profiles. RD pile wall is a solution which enables penetration of overburden soil, dense fill layers including stones and boulders, and embedding into the bedrock in one single operation. Several test installations and laboratory tests have been made to develop the system and to test and improve the water tightness of the wall. Beside these tests, RD pile wall has also proven its reliability in almost 70 projects. Largest project so far has been Pasila Tripla project in Helsinki, Finland. A permanent retaining wall with surface area of 18,000 m2 (193,750 ft2), excavation depth of 21 m (68 ft) and over 17 m (56 ft) of water pressure was made with 711 mm (28”) and 406.4 mm (16”) pile sizes. Piles were delivered to site in one piece with lengths up to 33.5 m (110 ft).INTRODUCTIONExcavations in cramped city centers and in between of existing buildings and other structures are facing more and more challenges. Installation of sheet pile walls is often problematic or even impossible due to obstacles in ground from old structures and due to demand to extend the excavations to even deeper and harder soil layers. Also installations of secant pile walls are facing difficulties due to cramped construction sites and constantly tightening execution times.On the other hand, an efficient and reliable piling technique suitable for the demanding soil conditions described above, percussion drilling, has been developed since the 1960’s, and especially from the mid- 1990’s, when the concentric drilling method with the ring bit and pilot was introduced. A new retaining wall application, the RD pile wall, was developed by combining that drilling method with the widely used retaining wall solution based on steel pipe piles and welded interlocks (a pipe pile wall normally installed with vibratory or impact hammers).PRINCIPLE AND MAIN BENEFITS OF THE METHODRD pile walls can be used in all soil conditions. Most beneficial the system is in extremely demanding soil conditions where the installation of traditional retaining walls is challenging or even impossible. The RD pile wall is a combination of drilled steel pipe piles and interlocking sections as shown in Fig. 1.Individual RD piles are connected to each other with interlocks welded to the piles on the automated welding line at the workshop. The matching dimensions of the drilling system and interlocking sections allow the installation of RD piles through stones and boulders and even into the bedrock, if necessary, in a single operation. Installation is done by a down-the-hole (DTH) hammer using the centric drilling system and oversized ring bits or a drilling system consisting of a pilot bit and reamer wings shown in Fig. 2."

Jan 1, 2017

By A. Tobey Yu, W. Joseph Schlitt, Alfred Weiss, Frederic L. Kadey, Louis Kuchinic

Introduction The February and April 1984 issues of MINING ENGINEERING have already provided introduction to the long-range planning efforts of the Society of Mining Engineers (SME). These efforts are intended to provide the basis for effectively maintaining and improving the Society in the face of the changes that are besetting the mineral industry. This requires that SME recognize what changes are occurring and determine how these will impact the membership. Then a plan must be developed and implemented so that the Society successfully meets the challenges of the next decade. The Board of Directors has charged the Long Range Planning Commission with the responsibility for meeting these goals. This article provides a summary of the work done by the Management and Organization Committee of the Long-Range Planning Commission. This committee's task was to analyze the Society's current organizational structure and management process. Then a set of recommended improvements was to be developed. In doing this, the Committee has been careful to operate under that popular axiom, "If it ain't broke, don't fix it." Thus, changes were not proposed simply for the sake of change, but only where the present system appeared to be less effective than desired. Bases For Action The Committee began by establishing a set of premises about SME and its membership. These premises provided the bases for subsequent actions and recommendations by the Committee. Highlights from the premises included: • The Society should be run on a business-like basis. However, its "business" is that of a not-for-profit scientific, technical, and educational public institution. SME enables professionals involved in or associated with the mineral industry to serve the public purpose of benefitting mankind. • The Society operates as a national (US) organization with transnational (worldwide) interests. It recognizes its obligation to make its goods and services available to minerals professionals throughout the world. In addition, the Society recognizes its obligation to translate technology for the "lay" public, who then also become users of its goods and services. • The Society's Board of Directors is the policy-making body of SME and has final approval of all programs. These responsibilities will become greater when the Society becomes a separate corporation. • At present, the Society provides the following goods and services: publications, meetings/programming/short courses, academic education support, information dissemination - internal and external, and individual member services. • Planning is an ongoing process. It is best performed on a decentralized basis. That is, each major service category should have a responsible group authorized to conduct planning for that category, subject to the Society's master plan and the Board's approval. • The Society is privileged to have highly qualified and motivated members who volunteer their time and efforts on behalf of the Society. The best of these volunteers should rise to the highest positions of leadership - the Presidency of the Society and Institute (AIME). • The Sooiety is strongly committed to the protection and promotion of the history, traditions, and identity of AIME and the use of AIME as the unifying forum for the Constituent Societies. Identification of Potential Problems Once the premises about the Society and its membership were well in hand, the committee began examining the many facets of SME's organizational structure and management process. This was done in order to identify problems or potential problems in these areas. After considerable review and discussion, 10 areas of potential concern were called out for more detailed study and possible recommendations for improvement. These 10 areas include: • A lack of continuity at the Board level and among officers due to the established turnover policy. • A series of subboards that serve, by practice, to diffuse management authority and accountability, rather than enhance it. • A question as to whether the dissemination of information has been adequately planned, organized, and staffed. • An apparent illogical divisional organization. Two divisions are discipline oriented and two are commodity oriented. • A regional organization that does not adequately fulfill its purposes. • Uncertainties about the per-

Jan 6, 1984

The first metal-mine accident-prevention course was prepared and published in 1942-45 as a series of seven miners' circulars (Nos. 51-57). The course has been broadened in scope, revised, and brought up to date and is being published as a similar series of seven miners' circulars (Nos. 51-57, revised) on accident prevention in metal and non-metallic mines. These circulars are as follows: Injury Statistics (Miners' Circular 51), dealing with general statistics on injuries from accidents at metal and nonmetallic mines, including causes, costs, and the use of investigations and reports of all injuries.

Jan 1, 1960

By Harold M. Wrigth

El siguiente estudio refiere al diseño y costo de construcción de las plantas concentradoras, así como el de plantas de beneficio realizadas en la provincia de British, Columbia. Para ello, el autor, quien diseñó aproximadamente 16 plantas para el tratamiento de minerales en el mencionado lugar, propone la dfusión y aplicación de este tipo de máquinas en nuestro país, considerando los tonelajes, las ubicaciones, resistencia del terreno, el flow sheet, para sentar las bases del diseño de los equipos.

Jun 20, 1954

By V. McLemore, A. Fakhimi, K. Donahue, D. Sweeney, V. Viterbo

In order to evaluate the relationships between weathering and durability and strength of rock samples from the Goathill North rock pile at the Molycorp Questa mine, NM, we conducted slake durability and point load tests. Slake durability index (ID2) values ranged from 84 to 98%. Point load strength index (Is50) averaged for all rock units ranged from 1.1 to 5.7 MPa. Results show a slight positive trend between ID2 and paste pH. Two populations of data are distinguishable when ID2 is plotted versus the percentages of chlorite, illite and internal friction angle. In general, Is50 values increase toward the interior of the rock pile. Preliminary conclusions indicate that the durability and strength of the rock pile material generally increase toward the interior of the rock pile. Pre-rock pile alteration and post-rock pile weathering history have affected the durability of the GHN rock pile samples.

Jan 1, 2007

By P. H. Derbyshire

The use of continuous flight auger piles has increased significantly in the U.K. to such an extent that it is now the most widely used method of constructing small diameter bored piles. This paper describes the improvements in equipment, techniques and particularly monitoring that have led to this growth. A review of the equipment in use describes how purpose built self erecting machines have been generally adopted. Improvements in ancilliary equipment are described. Concrete has almost completely replaced grout and techniques have been developed to extend the length of reinforcement that can be placed. Leading specialist contractors have developed instrumentation to monitor the construction of the pile (in terms of time, depth, torque, concrete pressure and flow) and keep a record for checking. A further significant development of this monitoring by means of sensors at various levels in the auger stem is described. The results obtained from this monitoring are reviewed and future developments discussed.

Jan 1, 1989

By Jeffrey M. Listak

This U.S. Bureau of Mines report describes the implications of in-mine ground control on the automated or remotely controlled operation of longwall mining equipment, Perhaps the greatest challenge to longwall automation researchers is the development of systems that will continuously function in the complex and unpredictable underground environment. The high degree of environmental variability, together with conditions brought about by the extraction process, makes complete automation of longwall mining a difficult task. The intellectual thought processes and split-second decision making required to avert disasters are lost when workers are removed from the face. As many mine operators can attest, minor problems, left unresolved, can eventually accumulate and lead to catastrophic consequences. The automation process will have to assess and manage various routine problems that are otherwise resolved through worker observation and experience.

Jan 1, 1990

By A. J. Kraemer

The twenty-fourth of a series of semiannual surveys pertaining to motor gasoline marketed in the United States was made by the Bureau of Mines in August, 1931, The first part of a report giving the results of that survey as they pertain to specification data is given in this paper. A companion report, Part II, is in preparation and will discuss the results off other determinations made on the samples, including octane number ratings on the individual samples (to be made by the Bureau of Standards) and results of the determination of gravity, color, doctor test, and "gum" content by the copper dish method and the Bureau of Mines steam-oven method. The retail price and the tax at the time Each sample was taken will also be retorted. History of Survey The Bureau of Mines made its first survey of motor gasolines sold throughout the United States in 1915,4 a second in 1917,0 and a third in April, 1919.0 These three surveys showed that during each 2-year interval the motor gasoline had become notably less volatile. In order

Jan 1, 1932

By J. B. Elizondo

This paper, which describes mining methods and practices at the Piokee mining unit and the Piokee expertmental mining project of The Eagle-Picher Co. in northeast Oklahoma, is one of a series being prepared by the Federal Bureau of Mines on mining methods, practices, and costs in various mining districts of the United States. The Piokee unit, comprising the Piokee, Rowe, Lucky Syndicate, and parts of the Netta White and Otis White leases, is in the SW1/4, W1/2NW1/4SE1/4, and W1/2SW1/4SE1/4 sec. 17, T. 29 N., R. 23 E., Ottawa County, Okla. (figs. 1 and 2), The 200-acre tract is adjacent to the town of Picher and near the heart of the Picher field of the Tri-State zinc-lead mining district.

Jan 1, 1959

By Onur Kacar

A numerical approach has been implemented to assess the settlements of pile groups bearing in clay. A three-dimensional finite element program has been utilized to model a vertically loaded spread footing, a single pile and a pile group. The soil-pile interaction was modeled with elastoplastic soil and interface elements. The model has been calibrated using a full scale load test results of the spread footing. The load transfer between the pile cap and the piles was assessed and compared with the measured load transfer. The predicted settlements for the pile group were compared with the settlements measured in the load test. Two analytical methods were adopted to predict the pile group settlements and they were compared with the measured values. The group effect determined from the analysis and load tests was compared with the interaction factor approach. It was shown that three-dimensional finite element approach can be successfully utilized to assess the soil-structure interaction and hence the load transfer between the piles and pile cap. Also, it was shown that the interaction factors method and equivalent footing method work well in the working stress range, however they underpredict the settlements at larger loads. INTRODUCTION The settlement and stress distribution of pile groups have been traditionally estimated based on load test results of single piles and accounting for the group effect using various approaches. The most widely used approaches are group interaction factor method, equivalent footing method and equivalent pier method. These approximate solutions are used very commonly in practice as full-scale load tests on pile groups are very expensive and time consuming. These approximate solutions are also adopted in design guidelines such as AASHTO LRFD Bridge Design Guidelines (2014) and FHWA Design and Construction of Driven Pile Foundations (2016). In this paper, a full-scale foundation load tests performed by Nagai et al. (1961) and reported by Koizumi and Ito (1967) is modelled using a three-dimensional numerical method. The settlements and the stress distribution on foundations were then compared with the traditional equivalent footing method and interaction factor methods.

Jan 1, 2018

By A. M. Ramalho

In the synthesis and sintering processes to obtain superhard materials, such as diamond and cubic boron nitride, deformable ceramic capsule is used as gasket to transmit and support the required high pressures and high temperatures, HPHT. The ceramics materials for these capsules should have special physics and chemical characteristics such as refractoriness, shear strength and compressibility. In this work, Bridgman?s anvil made of hard metal or speed steel was used to characterize some ceramics materials in terms of their maximum compressible thickness. Tests were also performed with different resin polymers used as binding mixture with ceramics powder. Chemical analyses and investigations through scanning electronic microscopic (SEM), X-ray and real tests for the synthesis of diamond were also performed. The results showed that local Brazilian calcite can be successfully used in the manufacture of HPHT gaskets.

Jan 1, 2006

By V. J. Sopuck, O. P. Lavin, Ian Nichol

"A major challenge of contemporary exploration geochemistry is the development of procedures that can locate blind mineralization or mineralization that sub-crops below a cover of transported overburden, the composition of which bears no relation to the underlying mineralization. Over the past few years, the possible existence of diagnostic geochemical features in the country rock associated with volcanogenic massive sulphide deposits has attracted increasing attention both on the local mine scale and on the regional scale. In the present investigation, the nature of the geochemistry of a number of Archean greenstone belts of the Canadian Shield is examined to determine the feasibility of distinguishing productive from non-productive areas of copper-zinc mineralization. The results indicate that productive areas are distinguishable from non-productive areas providing consideration is given to the effects of igneous differentiation on rock compositionIntroductionArchean massive sulphide deposits are an important source of copper and zinc, and to a lesser extent silver and gold, particularly in Canada. As in the case of most other forms of mineralization, there is a continual need to develop new techniques that will improve the chances of success in the search for these deposits. The majority of Archean areas in the northern latitudes are overlain by a variable cover of glacial overburden. Considerable progress has been made in the development of new geochemical exploration techniques for use in glaciated terrain, based on the detection of anomalous dispersion in the glacial overburden. In certain situations, however, as in the search for blind deposits or in areas covered by glaciolacustrine deposits, overburden geochemistry offers little hope for success. In the case of massive sulphide deposits, one possible solution may lie in the detection of anomalous geochemical signatures in the bedrock. Recognizing this possibility, attention has been directed to the investigation of the nature of lithogeochemical dispersion associated with massive sulphide deposits on both regional and local scales, to establish the potential of lithogeochemistry as an aid in the search for these deposits."

Jan 1, 1980

By Umay Cinarli, Ahmet Turan

High-energy consumption in primary aluminum production (from bauxite ores) makes secondary aluminum production (from metallic raw materials such as scrap and dross) very critical. Aluminum dross, as a waste, arises in pyrometallurgical processes, and it is the mixture of metallic Al, Al2O3, other metal oxides, metal halides, and some other compounds like AlN. Aluminum dross has two subgroups (white and black) with respect to its metallic aluminum content. White dross is a secondary aluminum resource because of its high metallic aluminum content, whereas black dross, having low metallic aluminum content, is generally disposed in dumping areas. In the present study, it was aimed to develop a simple technique to valorize aluminum black dross in the form of alumina-based ceramic materials through pyrometallurgical (calcination) and hydrometallurgical (leaching) operations. Moreover, thermochemical simulations were conducted by using HSC Chemistry 6.12 software to simulate calcination conditions. After leaching experiments, an alumina-based ceramic containing approximately 36.8% Al2O3, 61.4% MgAl2O4 with 1.8% Na2FeO4, which might be available to use as a spinel refractory in steel smelting furnaces, was obtained in the experiment carried out in a solution containing 10 mLH2SO4 and 40 mL distilled water (3.5 M). Moreover, the sinterability of the alumina-based ceramic was investigated at the temperatures from 1350 to 1550 °C. In the sample which was sintered at 1550 °C, a density value of 3.15 g cm−3 and a hardness value of 69.58 HV were measured.

Oct 26, 2020

By R. W. Chappell, M. W. Hills, R. L. Olsen

A stochastic approach was developed and applied to the Butte, Montana Hillside abandoned mining site for modeling stormwater runoff and subsequent receiving stream loadings. This approach enabled capture and quantification of the uncertainty associated with stormwater quality data and allowed the prediction of copper and zinc concentrations in the receiving stream caused by runoff from the Butte Hillside during storm events. Runoff flows and stormwater concentrations were input to the model as probability distribution functions. Monte Carlo simulation allowed prediction of expected instream concentrations in the form of cumulative distributions functions. The modeling results allowed evaluation of current best management practices (BMPs), targeting of future BMPs, and identification of key data gaps to fill during future sampling activities. This modeling approach is considered extendable to other active and inactive mining sites. Output from a model of this type is easily understood and can be used to communicate effective stormwater management to site regulators. Furthermore, application of this modeling approach will facilitate the development and implementation of a site-specific stormwater management plan and will optimize efforts to achieve standards for compliance with stormwater discharge permits.

Jan 1, 2002