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By R. V. Ramani

One area of study in the Coal Mine Injury Analysis project was to illustrate and enhance the ability of mine safety management personnel to apply analytical techniques to injury experience data and to justify requests for funds for safety enhancement actions on a cost/benefit and other quantitative basis. Four volumes of this final project report detail (1) the objectives and scope of the mine safety management research, (2) the results of literature review, and case studies, and (3) models developed for mine safety management. The four volumes are titled as Volume III: Mine Safety Management, Volume IV: Analytical Techniques for Mine Safety Management; Volume V: Mine Safety Management Case Studies and Volume IX: Training Cost Model. This volume deals with the development of a microcomputer based training cost model (TCM) which can be used to analyze training cost implications of various types of training. The model has been developed using Aston Tate's dBASE III plus language. The computer program and a test run of the model are presented in this report.

Jan 1, 1993

By CHARLES M. A. STINE

THE value of chemical research has been so thor¬oughly demonstrated in the last few decades that the general public has become "research-conscious" to an extent which allows the advertising agent and publicity man to make use of research as a selling point in his advertising campaigns. We thus see the advertisements of concerns in the most varied industries stressing the research which is back of their products. The reason for this "research-consciousness" of the general public. is primarily that the products of research have increasingly engaged public attention and have. revolutionized our daily life. When we. reverse the flight of .time and imagine ourselves-in the century previous to our own, we find that we are .without the automobile, the radio, the improved telephone and electric light, refrigerated transportation, the airplane, X-rays, and many other things now taken for granted. A generation ago we find gloomy prophets foretelling the certain over-population .of the world within a few decades and an insufficiency of food due to lack of the fixed nitrogen which is now so plentifully ours.

Jan 1, 1930

By R. Pelton, Z. Dai, S. Yang

ABSTRACT Hydrophobic polystyrene nanoparticles were evaluated as potential flotation collectors for pentlandite. The flotation of hydrophilic glass beads demonstrated the nanoparticles’ ability to induce flotation. Deposition of nanoparticles on glass surfaces increased the contact angle and enhanced adhesion of the beads to air bubbles. High flotation recoveries were achieved when 5–10% of the bead surfaces were covered with nanoparticles. Surface functionalization—the addition of vinylimidazole to polystyrene nanoparticle surfaces—caused the nanoparticles to selectively deposit onto pentlandite surfaces in the presence of Mg-Si slimes. Ongoing work includes attempts to identify specific applications where nanoparticle collectors might be cost effective. _ KEYWORDS Flotation, Nanoparticle collector, Coverage

Jan 1, 2014

By Cyril S., Smith

WE cannot but marvel at the fact that fire is necessary for almost every operation. It takes the sands of the earth and melts them-now into glass, now into silver, minium or other lead or some substance useful to the artist or physician. By fire, minerals are disintegrated and copper produced; in fire is iron born and by fire is it subdued; by fire, gold is purified; by fire, stones are burned for the binding together of the walls of houses.... Fire is the immeasurable, uncontrollable element, concerning which it is hard to say whether it consumes more or produces more." Thus wrote Pliny in his "Natural History," that great collection of fact and error which constitutes the principal contemporary description of Roman technology and which until the seventeenth century was the authority most often quoted and requoted by those who wrote on metals, as on many other subjects.

Jan 1, 1940

By R. A. Meister

The study on improving surface coat refuse disposal site inspections included surface inspections of 15 refuse disposal sites. Monthly aerial photos were taken of the sites and computer methods were used to determine elevation changes. Photogrammetric techniques that were used are described in detail. A comparison of the results of each of these inspection techniques is included. A detailed evaluation of the photogrammetric techniques was made and conclusions were drawn concerning the advantages and disadvantages of using aerial photography and photogrammetry as part of the inspection procedure. Operators' opinions of the aerial photography methods are included.

Jan 1, 1980

By S. L. Weber, D. E. Banks

"Silicosis was first reported by the ancient Greeks and is apparently as old as human history. The prevalence of this illness peaked in the last half of the 19th century and the early part of this century, when mechanized industry was developing and the relationship between dust exposure and disease was less well understood. Yet, even today in devel-oped countries, sporadic outbreaks of silicosis occur when workers are consistently exposed to silica particles of respir-able size (0.5 to 5.0 µm in diameter) at levels exceeding those recognized to be safe.Silicon dioxide or silica. is the earth's most abundant mineral. Silica is considered to be either free (i.e.. unbound to other minerals) or combined. Minerals with high amounts of free silica include quartz (including granite) flint. Chert, opal, chalcedony, and diatomite. Combined forms of silica are called silicates and include, among others, asbestos talc and kaolin.In the crystalline form, silica exists as quartz, cristobalite, and tridymite (Fig. 28). Of these quartz is ubiquitous in the environment and occurs as sand and as a part of many rocks. Cristobalite and tridymite occur naturally in lava and can be formed by the heating of quartz or amorphous silica. Cristo-balite is more tibrogenic than quartz. Amorphous silica is noncrystalline and, therefore, is relatively nontoxic and does not cause silicosis. It occurs as diatomite (skeletons of pre-historic marine organisms) or as vitreous silica (glass), the result of carefully melting and then quickly cooling free crystalline silica. Heating diatomite with or without alkali (a process known as calcining), forms cristobalite and adds the respiratory toxicity of free crystalline silica.There are many opportunities for occupational exposure to respirable crystalline free silica. Some of the commonly en-countered occupations in which the risk of silicosis exists are reported in Table 20.Silicosis. the pulmonary disease caused by the inhalation of silica particles of respirable size, is most commonly cate-gorized by findings on the chest radiograph. The most typical presentations simple silicosis and progressive massive fibrosis appear different radiologically but are grouped under the category of classic silicosis because they are a part of the radiographic spectrum of this illness. Radiographically, simple silicosis appears as small (less than 10 mm in diameter), rounded opacities, typically predominant in the upper lung zones. Progressive massive fibrosis is the result of the coalescence of these small nodular opacities and appears as larger opacities (more than 10 mm in diameter), again typicallydistributed in the upper lung zones."

Dec 1, 1995

By A. S. Watts

The Bureau of Mines has been conducting an investigation of the feldspar resources of the New England and North Appalachian States with a view to greater efficiency and economy in their utilization. Such an investigation was deemed necessary, not only because of the continued and increasing consumption of these minerals, but especially because of the demand for better technical control of the raw materials that are used by the white-ware industries of the United States. Most manufacturers of white pottery wares have only a limited knowledge of the origin, mode of occurrence, and methods of mining and preparation of the materials that they use. Heretofore, owing to a belief that the supply of raw material was unlimited, the manufacturer had concerned himself chiefly with the solution of the problems of manufacture. Within the past few years, however, it has been found that difficulties arise in manufacture which can be traced beyond the manufacturing process and are believed to be due to a need of better control of the materials used. Furthermore, as competition becomes more severe, more attention must be paid to selection of materials in order to minimize consumption and also to avoid unnecessary expense for transportation of material. Doubtless the lack of interest as regards these details has arisen from the fact that in the past a considerable proportion of the whiteware ingredients has been imported and the manufacturer has been forced to rely on the samples submitted and the general uniformity of the source of supply to insure against variation of the material. An extra precaution arising from this lack of definite knowledge still prevails in the common practice of never depending on one source of supply for anyone ingredient. Often the products of three or more producers are blended so that if anyone shall vary without warning the variation arising from its use will not be sufficient to ruin the ware.

Jan 1, 1916

[ENGLISH active earth pressure adapter additive adhesion admixture, addition adsorbed water aggregate air air entrainment air hose allowable bearing value allowable pile bearing load]

Jan 1, 1994

By Robert F. Shurtz

This paper suggests that pre-occupation with the random process model notised by geostatisticians may result in neglect of more promising techniques, especially since the random process model does not appear to be essential to current geostatistical procedures. This point of view is emphasized pictorially. To emphasize the potential of new techniques a simple application of the conventional Brownian function is described. The probabilities estimated in this truly random way are different from those estimated by Kriging

Jan 1, 1980

By Paul. D. Merica

I LIKE to look upon the award this year also as a recognition of the importance of metallic materials of construction to the engineer and of the active progress which I believe is continually being made in almost all branches of that field today. It has been said that metals are the material backbone of industry and technology. Well in that case, I suppose we metallurgists are industry's bonesetters. And it is possibly not inappropriate that we should occasionally give some atten¬tion to those bony structures of our industrial activities upon which engineers in other fields hang their manifold and striking creations. What is going on in the field of metals development? Well, in the first

Jan 1, 1938

By Horace T. Reno

This information circular surveys the iron are industry of the world. It presents a comprehensive statistical record through 1970 of the U.S. iron ore industry and world trade patterns. The supply position of the United States and the other principal industrial countries of the world are summarized; detailed information is given on iron are production, consumption, imports, exports, mine capacities, substitutes, properties, and uses. There is a generalized discussion of the technology of mining and smelting iron ore, with a selected bibliography on the current state of these arts. The circular contains a summary economic account of world iron are resources, and discussions of the structure of the domestic and principal foreign mining industries, iron are mine employment and labor productivity, research and development, legislation, government programs, and strategic factors.

Jan 1, 1973

By P. M. Daling, C. A. Geffen

The objectives of this study were to examine a representative cross section of formal safety analysis techniques developed for the nuclear and aerospace industries, to recommend those methods that would be suitable for application to the mining industry, and to include those methods in a user's manual. Volume XI of this report, the user's manual, describes several methods that were determined to be immediately transferrable to the mining industry. The handbook gives detailed instructions on appropriate application and utilization of the methods. Other techniques will require further development before they can be effectively transferred to the mining industry.

Jan 1, 1983

This report presents information developed during Bureau of Mines contract H0242016, "Mine Shaft Fire and Smoke Protection Systems" from May, 1974 through June, 1975. Purpose of the metal and nonmetal health and safety project was to evaluate mine shaft fire and smoke hazard problems, and to develop and demonstrate a low-cost, reliable mine shaft fire protection system that would protect against such hazards and would be applicable to a majority of metal and nonmetal mine shafts, including raises and winzes, especially in deep mines. Program effort proceeded through five phases, culminating in the successful in-mine fire demonstration of a prototype system. In addition to this final report, a film is available which depicts components of the system and its successful shaft fire testing at an underground mine.

Jan 1, 1975

By Jr. Kermit Allen

A study was conducted for the AEC to determine the feasibility of constructing an unsupported 315 foot diameter spherical cavity at a depth of 2,700 feet in a salt dome. A cavity of this size and shape has never been attempted. It was determined that the three basic essentials for solution mining; adequate salt, fresh water, and a means of brine disposal were available at the Tatum Salt Dome in Lamar County, Mississippi. Assuming a large, unsupported mined opening of the size and at the depth required would remain stable, the most practical method of providing the cavity using solution mining techniques is by use of a movable blanket of air to control the water level to properly shape the cavity while removing the insolubles either with jetting or by conventional mining methods. It is estimated that, using the jetting method of insolubles removal, the cavity can be constructed in 24 months for approximately $7 million. Using conventional mining techniques to remove the insolubles and shape the final cavity, it is estimated that the cavity can be constructed in 36 months for approximately $12.6 million.

Jan 1, 1968

By W. T. Abel

The difficulties associated with wet-processing fine size coal led the Bureau of Mines to investigate a dry process for removing pyrite from coal pulverized to powerplant fineness. The dry process that was investigated consists of two cleaning steps: First, centrifugal separation is used to remove a fine, pyrite-depleted portion as a product; second, the remaining coarser, pyrite-enriched portion is taken to electrostatic separation in which pyrite is concentrated and rejected. Ball milling and Hardgrove milling were used to pulverize the coal. Three coals from the Pittsburgh seam were treated by the dry-removal process. Over 55 pct of the pyrite, which amounted to 70 pct of the available pyrite, was removed in a reject of 10 to 20 pct from one of the coals. Similar treatment of the other two coals removed about 35 to 50 pct of the pyritic sulfur, which amounted to about 70 pct of the available pyritie, sulfur from these coals. Both centrifugal and electrostatic separations were more efficient when pyrite particles were as large as possible. Separation efficiency was improved by confining the particle size of the feed to a relatively narrow range and by avoiding excessive amounts (more than 10 pct) of dust in the electrostatic range. The removal efficiency was increased with the use of stage grinding.

Jan 1, 1973

By J. Sikamo, A. Mwanza, C. Mweemba

"The Zambian copper mining industry as we know it today had its genesis in the 1920s. Consistent private sector-driven investment in the industry over a period of over 50 years in exploration, mine development and operation, development of minerals processing facilities, building of infrastructure for pyrometallurgical and hydrometallurgical processing, with attendant support facilities, including building of whole new towns, resulted in copper production rising to a peak of 769 000 t in 1969, providingover 62 000 direct jobs. The industry was nationalized in 1973 and remained in government hands for just over 24 years. During this period, the industry experienced a serious decline in production levels, reaching the lowest level in the year 2000 when production was 250 000 t. An average of just under 2000 jobs were lost every year in the 24-year period, reaching just over 22 000 direct jobs in 2000.Following the return of Zambian politics to pluralism and liberalized economic policies, the government decided to privatize the mining industry. The process started in 1996 and by the year 2000 all the mining assets had been privatized. The new investors embarked on serious investment to upgrade the assets and to develop greenfield mining projects. Fourteen years later and after more than US$12 billion investment, production levels increased year-on-year to a peak of 763 000 t in 2013 with direct jobs reaching 90 000.This paper discusses the impact of the mining industry in Zambia on the economy in areas such as employment, support for other industries, direct contribution to the national gross domestic product (GDP), foreign exchange earnings, and social amenities. The paper also focuses on the performance of the mines during these periods vis-à-vis mineral availability, mineral grades and complexity, new technologies, and human capital. This is looked at particularly in the light of current challenges the industry is facing. Suggestions are proposed on how the industry can be nurtured to continue being a major driver for the Zambian economy and a major player in the international copper mining business."

Jan 1, 2016

By Christine Hansen

?Kiss my Asteroid? Unofficial Title Human life is tied to minerals It?s worth noting that: The living human body consumes minerals. The minerals we take in multivitamins show the close linkage between human beings and mineral resources. Unlike tourism or specialized manufacturing, a human being could not live without mineral consumption. Minerals and their consumption is a tangible part of human life.

May 1, 2013

By Walter F. Atkins

Fair market value, in the legal sense , is the price which a prudent and knowledgeable buyer and a prudent and knowledgeable seller, acting without constraint or compulsion , will agree upon to exchange an asset. In the ordinary commercial or engineering usage, the term may imply simply the market value or a reasonable and equitable price. The engineer evaluator who is called upon to express an opinion about the fair market value of an asset may be able to base his estimate on the sale price of similar assets or on the market values of stock. Frequently such indicators of value are not available and the evaluator must devise other means of appraisal. Mineral resource properties may be thought of as having value by virtue of the existing or potential ability to produce at a profit. Conventional procedures permit the computation of the present value of future revenues having due regard for the time value of money and the risks attendant upon the realization of the venture. Such computations have gained wide acceptance as a basis for the estimation of fair market value.

Jan 1, 1977

By Richard G. Geyer

One aspect of a program to improve the chances of survival following coal mine disasters is the development of a communications sys tem which will allow surviving miners to make their circumstances known to rescue teams. At present, it appears that an electromagnetic system may be most practical. The development and design of an effective electromagnetic communications link for signalling between mine workings and the surface requires knowledge of pertinent physical properties of the rocks overlying the mine workings and the characteristics of the ambient noise against which a communications signal must be recognized. Knowledge of the overburden electrical transmission properties is useful not only for determining a practical operating transmitter frequency at a given mine, but also for ensuring the best possible electromagnetic coupling for routine or emergency communication purposes. Field studies of the electrical transmission properties of the overburden of coal mines in Colorado, Illinois, and Pennsylvania generally show that a relatively uniform and unimodal electrical conductivity distribution exists provided that the region has not been subject to considerable structural or metamorphic deformation such as that observed in the Gary District of West Virginia. Measurement s of ambient surf ace electromagnetic noise levels at several mines in Colorado, Illinois, and West Virginia were taken and analyzed and are presented in the form of amplitude histogram plots both as a function of frequency and time of day. These amplitude histograms may be used in conjunction with overburden resistivity data in implementing an uplink communications beacon system which will yield a specified signal- to-noise ratio at the surf ace. Numerous C .W. field transmission tests were made in various coal mining environments with use made of either a buried vertical-axis transmitting loop or a short insulated grounded current line. These transmission tests were made from 20 Hz to 20,000 Hz in frequency and at several geographic surface receiving sites. The results of these field measurements show, in general, good agreement with theoretically calculated results. Since the produced surf ace magnetic field from a buried vertical-axis loop source or the produced surface horizontal electric field from a buried horizontal current line show better agreement with theoretical results, they could be used for beacon location system. One criterion would be in detecting the equatorial and polar null lines of the horizontal electric field component which is normal to the direction of emplacement of a buried transmitting line current source. A second criterion would be in the surface mapping of the maximum in the vertical magnetic field directly over a vertical-axis loop transmitter and the associated null is the vertical magnetic field at a horizontal offset distance which is about 1.4 times the depth of burial of the transmitter. Finally, a third criterion would lie in the surface mapping of the null in the horizontal magnetic field directly over the vertical-axis beacon and the associated maximum in the horizontal magnetic field at an offset distance from the transmitter axis of half the depth of burial of the loop transmitter. In mapping the vertical magnetic field over a buried vertical-axis loop transmitter, the size effect of the transmitter loop must be taken Into account when the separation distances between the transmitter and receiving sensor are less than ten times the effective radius of the source loop; increasing the size of the transmitting source relative to the source-receiver separation distance shifts the null in the vertical magnetic field to greater offsets. In mapping either the vertical or horizontal magnetic field over a buried vertical-axis loop transmitter, care should be exercised in ascertaining that measured nulls and maxima are along radials through the axis of the buried source loop. For the main part, coupling experiments show that ambient electromagnetic noise in coal mining districts is less of a problem above 1000 Hertz. But secondary and perhaps undesirable maxima and null phenomena (as well as penetration problems) would occur in many coal mine provinces in the behavior of the surface horizontal magnetic field (over a buried vertical-axis loop transmitter) if transmission frequencies as high as 10 kHertz were used.

Jan 1, 1974

By Tom Treleaven

The success of any blast is dependent on the accuracy of the blast design and the field controls used on the shot. This point cannot be over emphasized because when the geometry is not measured and/or field controls are not properly implemented, it can often have devastating effects on the final blast results. Thus drilling accuracy, tiont row burden control, explosive confinement, energy distribution, explosive selection, timing and structural geology become critical parameters in the design of successful blasts. Understanding the actual dynamics of the blast and why certain results were achieved is the fast step in optimizing a blast design. As stated by R. Frank Chiappetta, “Of all the blast monitoring systems available today, high speed videography still remains as the best stand alone instrumentation system for blast diagnostics.” Over the past years I have analyzed hundreds of blasts using either high-speed lowcams (500 frames per second) cameras or standard digital (30 frames per second). These analyses confirm, without a doubt, that shot geometry, in combination with structural geology, is the most important factor in overall blast results. Drilling accuracy is the single most important component in efficient blasting. Having equal mass associated with an equivalent energy is the basis in which blasts are designed. When drilling inaccuracy or borehole deviation occurs, not only is the energy unevenly distributed, but the basis of all design calculations becomes invalid. Over the past several years, quarry and mining operations have employed the use of boretracking measuring devices to measure borehole deviation and hole toe locations. In cases of operations using top hammer drills, it was discovered that the amount of deviation was significant and far greater than they believed they had. Set up error, improper drilling techniques and bit wear were some of the contributing factors. Through video anaysis of boretracked blasts, blast results were directly linked to drilling ..accuracy. The comparisons here took into account blast design, energy factors and hole sequencing.

Jan 1, 2000