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By Clyde L. Holmberg, Paul Zinner

"INTRODUCTION In view of the large tonnage of low-grade iron ore and iron-bearing material known to exist at the western limits of the Gogebic range, the Bureau of Mines undertook an investigation of the area for the purpose of evaluating the iron-bearing formations as sources of iron for possible future utilization.After 6o years of exploration an, development on the Gogebic range, the area investigated by the Bureau represents the known western limit of direct-shipping ore mined from operations on the Gogebic range.An area about 2 miles in length between the villages of Pence and Iron Bolt in Iron County, Vic., was selected for investigation, and trenches wore excavated through the overburden and fully across the iron-bearing formation to obtain 108 bulk samples for beneficiation tests. Exhaustive tests involving gravity and flotation methods, magnetic separation, and magnetizing roasts followed by magnetic separation were conducted on the samples to determine the ammability of the individual formations and the entire iron-bearing zone to beneficiation.Empirical data on the character and mineral content of the formations arc tabulated herein, as well as the results of the beneficiation tests."

Dec 1, 1947

By J. M. Benson

Metal powder compaction offers unique advantages in the manufacture of net-shape components using techniques such as laser sintering, conventional press and sintering, metal injection moulding, direct rolling, direct forging, and hot isostatic pressing. If the output from the primary metal production process is in powder form, then considerable cost and energy savings can be realized by direct conversion to semi-finished or final shapes. This possibility exists for titanium and possibly also for Ta, Zr, Hf, and Nb metals. However, these attractive benefits are associated with some significant risks. The high surface-to-volume ratio of powder particles coupled with the reactive nature of these metals means that special care must be taken when handling them. Powder explosions are unfortunately still a regular occurrence internationally and these often result in serious injury and loss of life. Even seemingly 'safe' compounds such as sugar, flour, and grain can be extremely hazardous when handled or milled and dust clouds are produced. In addition, exposure to airborne particles can have adverse effects on the human body, especially when particles are inhaled on a regular basis. Furthermore, the medical consequences of these are not fully understood, especially in the case of nanoparticles. The impact is often not observed immediately and debilitating illnesses may emerge only years or decades later. As far as is known, there are no South African guidelines for handling of metal powders. This paper attempts to provide an awareness of the risks associated with metal powders (including those produced indirectly by other metalworking/finishing operations) as well as some guidelines for their safe handling, based on international best practices.

Jan 1, 2012

By Roy Peratrovich

An innovative cost-saving design for a 1,100 ft bulkhead on the Tanana River at Nenana in central Alaska won Alaska Construction & Oil magazine's Construction Achievement Award. The designers utilized materials available nearby at low cost. They planned sheet pile enclosures, self-anchored back into shore without cell closures. They made it practical for inexperienced local workers to do the building. And they completed the project on time and below a reduced budget.

Jan 1, 1985

By William R. Yernberg

What a difference a year makes. One year ago, the iron mining industry and the steelmaking industry in the United States were in trouble. Many companies were in bankruptcy, and talk of plant and mine shutdowns was rampant. At that time, it seemed difficult, if not impossible, to remain competitive with imported steel. In addition, the World Trade Organization declared as illegal the tariffs placed on imported steel. And many questioned the viability of the ironmining and steel industry in the United States. At that time, global economic conditions were the main contributors to the industry’s problems. However, since last year’s meeting, changes in global economics have actually helped the steel industry in the United States. Heavy global demand for steel has caused raw-material shortages worldwide. Much of the increased demand is a result of the economic boom in China. In addition, because of a weak U.S. dollar and higher international freight rates, steel imports into the United States have been reduced to about 50 percent of recent levels. These factors have contributed to a rebirth of the U.S. iron mining and steel industries.

Jan 1, 2004

By Howard E. Parkinson, John N. Murphy

The past five years have seen communications techniques and hardware developed by the Bureau of Mines and its contractors increasingly brought into use in U.S. mines. The Bureau philosophy has been to help develop and introduce new hardware that goes as far as possible toward meeting the mining industry's needs. The Bureau programs are also designed to provide continuous fallout of new communications capabilities which are introduced to the mine operators as they occur. As more progress is made in meeting mine communications needs, it is hoped that the mining industry will readily adopt the equipment and techniques that it finds most useful in meeting its individual needs. This paper reports on recent advances achieved in the development of improved mine communications systems. In May 1975 the U.S. Bureau of Mines (USBM) conducted a mine communications technology meeting to provide a brief overview of the USBM communications technology developments in the past 5 yr. This meeting lasted for 1 1/2 days. Therefore, I have elected to narrow this paper to a brief review of recent underground mine communication developments. The following will be discussed: 1) Ultra-high frequency (UHF) radio for fan hole drill operators;

Jan 1, 1978

By Floyd B. Bowen

Pumping methods are used, almost exclusively, to transport materials in the mining, beneficiation and chemical processing of phosphate rock in the Florida phosphate pebble field. Matrix pumping systems capable of pumping 15,000 g.p.m., transporting 15,000 long tons (dry) per hour, are now in use. They utilize 16-by 48 Yz -in. pumps, driven by 1.250-h.p. motors, discharging into pipelines 20 inches .in diameter .and sometimes several miles in length. As an average, it is necessary to pump 3 tons of matrix to the beneficiation plants, and to dispose of 2 tons of sand tailings and clay as waste, in order to produce 1 ton of shipping-grade rock. The washers and flotation plants, where the clay and phosphate and silica particles are separated, require the movement of large volumes of slurries with densities ranging from 2-3 per cent to 45 per cent solids, by weight. Extensive waste disposal systems require the pumping of dilute clay slurries in quantities of up to 50,000 g.p.m.,

Jan 1, 1963

Ferrous and Nonferrous Physical Metallurgy Established as a Division April 26, 1918 T A Read, Chairman O T Marzke, Past Chairman J H Jackson, Senior Vice-Chairman David Swan, Vice-Chairman D C Johnston, Secretary-Treasurer AIME, 29 West 39th Street New York 18, New York

Jan 1, 1960

By Arnaud-Guilhem de Loze

Este artigo apresenta uma ferramenta de simulação computacional desenvolvida com o objetivo de auxiliar a adoção de melhores práticas de controle do forno durante períodos sem produção. O sistema desenvolvido permite simular as temperaturas do revestimento refratário de um forno de tratamento térmico de tubos em função da evolução da temperatura da atmosfera interna em diferentes cenários. O simulador foi desenvolvido baseado em um modelo matemático dinâmico validado, que utiliza um sistema de equações de transferência de calor discretizadas. Realizou-se a validação desta ferramenta computacional com a utilização de dados reais de uma campanha de medição de temperaturas. A comparação dos resultados apresentou pequeno erro entre simulação e valores reais coletados. A utilização desta ferramenta auxiliou a definição de estratégias de controle do forno durante períodos improdutivos, possibilitando redução do consumo de energia e retomada da produção com garantia da qualidade do produto.

Aug 17, 2017

By Laurance L. Oden

The Bureau of Mines is developing nickel catalysts for converting synthesis gas derived from coal to synthetic natural gas. The present report describes the relationship between the composition of aluminum-nickel alloys in the composition range NiAl3 to Ni2Al3 equilibrated at 840° C and the properties of catalysts obtained from them. Methanation activity was determined in the temperature range of 300° to 360° C in a flowing gas stream containing 1 pct CO, 8 pct H2, and the remainder He. One part per million of H2S was added to the gas stream at 400° C to evaluate the susceptibility of catalysts to sulfur poisoning. The total surface area was measured by the adsorption of nitrogen at liquid nitrogen temperature, and the active surface area was measured by the adsorption of hydrogen at room temperature. Total surface area and active surface area were found to increase with increasing proportion of aluminum-saturated Ni2Al3 in the precursor alloy, but methanation activity and resistance to poisoning by H2S were nearly constant. However, the methanation activity of the catalyst prepared from stoichiometric Ni2Al3 was less than half that of the other catalysts.

Jan 1, 1978

By Foster Fraas

One of the lithium minerals most widespread in the earth's surface is spodumene (Li2O-A1203-4Si02) a lithium aluminium silicate. For some time, deposits of this mineral were known to exist in the Black Rills of South Dakota, but it was only quite recently that Hess4/ pointed out the great magnitude of the low-grade e deposits it s in North Carolina. The theoretical lithia (Li20) content of spodumene is 8.04 percent. The only other minerals with such high lithia content are the phosphates, but these occur only in pockets and are not in extensive deposits5/. Actually, however, the lithia content in spodumene is never found to be this high, being nearly always below 7 percent for the pure mineral, and part of the lithia is apparently replaced by other alkalies.

Jan 1, 1937

By M. C. Fuerstenau, D. N. Collins, R. B. Bhappu, D. N. Moir

D. N. Moir (Senior Scientific Officer, Warren Spring Laboratory, D.S.I.R. Stevenage) and D. N. Collins (Scientific Officer, Warren Spring Laboratory, D.S.I.R., Stevenage, England) — During work on the petroleum sulphonate flotation of beryl in 1959 at Harwell, and subsequently at Warren Spring Laboratory, effects similar to those mentioned by the authors were noticed. Brief details of some of this work were given to the 6th International Mineral Processing Congress at Cannes.' It is interesting to note that the authors experienced strong activation effects with Fe+++ ions on beryl when using petroleum sulphonate collectors. This phenomenon was of interest in our work when

Jan 1, 1963

As it is probable that a large proportion of the members of the Institute attending this meeting are connected with the metalliferous side of mining, the writer thought that, as coal and coke are required for various purposes in considerable quantities by their companies, some particulars of the coal industry might be of interest, especially when visiting such an important coal-mining centre as Newcastle. It is proposed to deal with the matter from the mining and economic point of view, as the geology has been so well and exhaustively dealt with in various publications referred to in the bibliography at the end of this paper. In the immediate vicinity of the city of Newcastle the collieries are gradually being abandoned, and during the past few years the Wickham and Bullock Island, Stockton, Hetton, Newcastle Coal Mining Company's "B," and the Australian Agricultural Co's Sea pit, have disappeared from the coal-producing list of collieries. AIl of these collieries worked the Borehole seam, from which, up to date, the largest quantity of coal has been produced in the northern district.It is the bottom seam of any present commercial value in the Upper or Newcastle coal-measures, and although the coal-in this seam has not been entirely 'exhausted in the collieries referred to, they have been abandoned for various reasons. For example, although about 60% of the seam (18 to 20 ft. thick) was left in the workings in the form of rectangular pillars under the city of Newcastle, this was not sufficient to 1?revent'the subsidence which took place about twelve years ago.Again, large quantities of coal in the Borehole seam have been left to protect the shipping arrangements at the Dyke, and other...

Jan 1, 1918

By Y. van der Grijp

The applicability of a stochastic approach to the simulation of gold distribution to assess the uncertainty of the associated mineralization is examined. A practical workflow for similar problems is proposed. Two different techniques are explored in this research: a Direct Sampling multi-point simulation algorithm is used for generating realizations of lithologies hosting the gold mineralization, and sequential Gaussian simulation is applied to generate multiple realizations of gold distributions within the host lithologies. A range of parameters in the Direct Sampling algorithm is investigated to arrive at good reproducibility of the patterns found in the training image. These findings are aimed at assisting in the choice of appropriate parameters when undertaking the simulation step. The resulting realizations are analysed in order to assess the combined uncertainty associated with the lithology and gold mineralization.

Jan 1, 2015

LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION Transactions Number Place Date Vol Page 1 Wilkes-Barre, Pa May, ?71 1 3 2 Bethlehem, Pa August, ?71 1 10 3 Troy, N Y November, ?71 1 13 4 Philadelphia, Pa February, ?72 1 17 5 New York, N Y May, ?72 1 20 6 Pittsburg, Pa October, ?72 1 25 7 Boston, Mass February, ?73 1 28 8 Philadelphia, Pa May, ?73 2 3 9 Easton, Pa October, ?73 2 7 10 New York, N Y February, ?74 211 11 St Louis, Mo May, ?74 3 3 12 Hazleton, Pa October, ?74 3 8 13 New Haven, Conn February, ?75 3 15 14 Dover, N J May, ?75 4 3 15 Cleveland, 0 October, ?75 4 9 16 Washington, D C February, ?76 4 18 17 Philadelphia, Pat June, ?76, 5 3 18 Philadelphia, Pa October, ?76 5 9 19 New York, N Y February, ?77 5 27 20 Wilkes-Barre, Pa May, ?77 6 3 21 Amenia, N Y October, ?77 6 10 22 Philadelphia, Pa. May, ?78 6 18 23 Chattanooga, Tenn May ?78 7 3 24 Lake George, N.Y. Oct. ?78 7 25 Baltimore, Md. Feb. ?79 7 26 Pittsburgh Pa, May ?79 8 27 Montreal, Canada Sept, ?79 8 28 New York, N.Y. Feb, ?80 9 29 Lake Superior, Mich Aug, ?80 9 30 Philadelphia, Pa. Feb, 81 9 31 Staunton, Va May, 81 10

Jan 1, 1923

This briefing was sponsored by the Bureau of Mines to summarize ongoing and recently completed chromium-chromite research and resource assessment activities by the Bureau. Through the series of 18 presentations compiled herein, Bureau personnel covered a wide range of topics including U.S. chromite and chromium trends and usage patterns; foreign and domestic resources; and research activities on mineral characterization and beneficiation, chemical and pryometallurgical processing of chromite and chromium-bearing wastes, new low-chromium alloy and coating substitutes, corrosion- and oxidation-resistant stainless steels, and chromium-containing refractories.

Jan 1, 1986

By Giuliana A. Zelada

This paper reports on a study of 43 compression load tests (five fully instrumented) and ten pullout tests of auger cast-in-place (ACIP) piles in sand. Eight design methods reported in the literature were used to predict the measured pile capacities. Ultimate load capacities of the ACIP load tests were determined using two different definitions of ultimate capacity and compared with predictions. Load transfer behavior was determined from a study of the fully instrumented pile tests and compared to predicted values. Recommendations are made regarding the design approach most appropriate for these foundations and the best procedure for estimating ultimate capacity from pile load tests.

Jan 1, 2000

By H. E. Cook

The Ising model for the internal energy of a binary alloy has been used to obtain a general equation for the critical resolved shear stress of partially ordered crystals. The equation expresses the stress in terms of the Warren "alphas " and can be used to estimate the variation in strength with order without the assumption, present in the original formulation of this problem in terms of domain size, that order is complete within each domain and that the domains are of ungorm size and shape. In addition, it is the general equation, according to the Ising model, for strengthening by short-range order. Two applications of the equation are considered: One is an estimate of the variation in strength of CkAu with long-range order. The other is an estimate of the variation in strength of FeCo with quench temperature. Reasonable agreement is found with the variations reported in the literature. When the internal energy of an alloy crystal depends upon the distribution of solute, the strength of the crystal will also depend upon it because a portion of the applied stress for plastic deformation will be: where V is the volume of the crystal and E(E) is the energy change associated with the solute redistribution caused by the plastic strain, E. We expect T to equal zero for a crystal having a random arrangement of solute because the arrangement would remain random after plastic deformation. Likewise, we expect it to equal zero when the crystal is perfectly ordered because the motion of paired dislocations found in such crystals does not disrupt order. However, when short-range order exists or when long-range order is incomplete, plastic deformation will decrease the amount of order and additional work, proportional to the ordering energy, will be expended. Fisher' estimated T for crystals having short-range order by assuming an interaction energy between neighboring atoms and estimating the change in the number of unlike neighbors as a dislocation moved through the crystal. (His analysis was limited and several workers2"6 have since given more complete ones.) Fisher minimized the importance of a strengthening mechanism of this type for paired dislocations in a structure having long-range order. ~ottrell,' however, pointed out that T could be appreciable for ordered crystals having antiphase domains. He attributed the strengthening to the increase in surface energy of the domains as they were cut by paired dislocations. Ardley,' in his test of Cottrell's theory, found that r for Cu3Au crystals obeyed the equation: for 1 > t where 1 is the domain size, t is the domain wall thickness, and y is the surface energy of an antiphase boundary. His experiments represent the classic confirmation of the strengthening mechanism proposed by Cottrell. However, the assumptions involved in using Cottrell's theory are valid only for large domain size in CU~AU,~"~ i.e., when Eq. [2] reduces to: For small domains, ~linn~ has questioned Ardley's assumption that order was complete, and, indeed, Stoloff and ~avies" fpnd it incomplete until a size of approximately lOOA was reached. Even when the order within a domain is complete, it is not obvious how one determines the appropriate value for I in a structure where domains vary in size and are irregularly shaped. The purpose of this paper is to estimate T without restrictions upon the degree of order and domain shape. Our major assumption will be the use of a generalization of the model proposed by Bethe" (the Ising model) for the internal energy. This will in fact allow us to combine the theories for strengthening by short-range order and by antiphase domains into a single, general formalism. We will use the results to estimate the variation in strength of Cu3Au crystals with long-range order8 and the variation in flow stress of FeCo crystals with quench temperature.12'13 INTERNAL ENERGY For simplicity, we restrict our considerations to those binary solid solutions which can be described as an arrangement of atoms on a Bravais lattice. An atom site will be indexed by three numbers (PI, pz, p3) determined by the vector: from the origin fixed at atom (0, 0, 0) to the atom site where a', an, and a, are the lattice translation vectors. We write: For the energy of the crystal where pi(p) is the probability (either zero or one) of finding an atom of type i (i = 1, 2) at site (p), which is shorthand for (pl, pz, p3) and pj(p + r) is that for an atom of type j (j = 1, 2) at the site (p + r), which is shorthand for (pl + rl, The coupling parameter, resents the energy associated with the pair Pi(p), Pj(p + r). The crystal is assumed large enough so that surface effects can be neglected; therefore, trans-lational and inversion symmetry require the coupling parameters to obey the relations

Jan 1, 1969

By A. B. Cecala

A few years ago, the National Institute for Occupational Safety and Health and Unimin Corporation developed a clothes cleaning system that is able to quickly, effectively, and safely remove dust from a worker?s clothing without dust exposure to the worker, the work environment, or co-workers during the cleaning process. To perform the process, a worker enters a cleaning booth and activates an air spray manifold which blows the dust from the worker?s clothing. Since the cleaning booth is under negative pressure, all the dust and product removed are contained. In the original design, this dust-laden air was exhausted to a dust collector system. However, since most operations do not have excess dust collector capacity, it was decided to determine an alternative method to provide for a stand-alone cleaning system. This was achieved by ducting the exhaust outside the plant and into the atmosphere. This technique was recently tested and shown to be a viable method to provide for a stand-alone clothes cleaning system.

Jan 1, 2009

By Slavoljub D. Maksimovic

The Bureau of Mines, through a memorandum of agreement with the State of Ohio, tested a method of constructing seals in abandoned mine openings in Ohio by means of pneumatic stowing of crushed limestone and gravel with sand. A total of five openings and one shaft were back-filled. Pneumatic stowing uses compressed air to convey material through a pipeline and into the mine opening. The stowing equipment consists of a power supply, a blower, a feeder to inject the material into the pipeline through an airlock, and a nozzle for directing the placement. Material is ejected from the nozzle at high velocity, creating a high-compaction fill upon impact. Well-graded aggregate up to 2 inches in diameter and having sufficient fines is used as fill. The stowing method is safer and faster than conventional methods, is cost competitive, prevents trespass into abandoned mine openings, and eliminates or reduces the exposure of workers to possible hazards since the discharge nozzle can be kept at the mouth of the opening. The equipment is mobile, and, with some modification, the technique could be widely used for sealing abandoned and active mine openings, even in remote locations and during severe weather conditions.

Jan 1, 1982

By J. David Lowell

This paper describes the geology of the Kalamazoo copper orebody discovered in the course of an exploration project carried out by Quintana Minerals Corporation under the author's direction in an area immediately southwest of the San Manuel mine, Pinal County, Arizona. In the period 1943-1947, exploration projects were carried out in the San Manuel area by the U.S. Bureau of Mines and Magma Copper Company which resulted in the development of the San Manuel underground block-cave mine which is now in production at a rate of 41, 000 tons per day. Mining claims covering the area immediately west of the San Manuel orebody were staked in 1946 by Frank F. Salas, R. A. Buzan, H. G. Buzan, and W. C. Buzan of Mammoth, Arizona. These claims were optioned to Martha Purcell in 1946, and in the period of 1947-1958 seven churn drill holes ranging in depth from 1,400 to 2,950 feet were drilled by Mrs. Purcell. These holes did not intersect ore and no further deep exploration was attempted prior to the Quintana Minerals project which began in August, 1965, and which is described in this report. The Kalamazoo deposit is in Sections 3, 4, 9, and 10, T 9 S, R 16 E, Pinal County, Arizona, and it is reached by driving seven miles east from Oracle, Arizona (Figure 1) . The writer is indebted to Corbin J. Robertson and Ronald B. Thompson who participated in the exploration planning of this project and to a number of other individuals who contributed to its execution and management. Petrographic work by J. M. Guilbert was used as a basis for rock and alteration classifications.

Jan 1, 1968