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By J. H. East, D. Harrington

"INTRODUCTION Considerable interest has been shown in the prospective use of Diesel-powered haulage equipment in both coal and non-coal mines. Foreign technical magazines have devoted considerable space to discussions of the use of Diesel locomotives in European mines and some mention of it has been made in technical papers in the United States. The Bureau of Mines has extensively tested the gases produced in the exhaust of the Diesel engine under various atmospheres and conditions of use; it has established a schedule of tests for permissibility of Diesel engines for use in underground coal mines, including, gassy or dusty mines.This publication provides information as to the successful use of Diesel-powered equipment underground workings in the United States and Europe, briefly discusses the characteristics of some of the toxic gases found in the exhaust of Diesel engines, and points out that Diesel-powered equipment can be used with reasonable safety in underground minus if necessary and entirely feasible precautions are taken."

Apr 1, 1947

By J. M. Stuve

Low-temperature adiabatic heat-capacity determinations were made by the Bureau of Mines in the temperature range from 5 to 300 K for the two crystalline modifications of zinc sulfide, sphalerite (ß) and wurtzite (a). The entropy at 298.15 K of sphalerite was evaluated as l4.02±0.04 cal/deg mole and wurtzite, l4.06±0.04 cal/deg mole.

Jan 1, 1974

By Wilbur Duvall

For the past few years the Applied Physics Branch has been investigating, experimentally, the generation and propagation of strain waves in rock. The strain waves are produced by the detonation of a high-velocity explosive placed in a small cavity in the rock. Strain gages mounted in the solid rock surrounding the cavity record the strain pulses propagated away from the source. Numerous strain-wave pulses have been recorded in different rock types for charges of various sizes and at various distances from the charge. Analysis of these records has shown, among other things, that there is associated with the strain wave a characteristic pulse width. This pulse width is dependent on the rock type and the distance from the shot point to the gage, but is apparently independent of the charge size or cavity size. Recent published literature on the generation and propagation of seismic waves indicates that the characteristic frequency of an elastic wave generated by an explosion should be a function of the rock type and the size of the cavity created by the explosion. Also, internal friction in the rock would produce absorption of high-frequency components, which would cause continual change in the shape of the pulse propagated. As the experimental data did not verify the expected change in pulse shape with cavity size, a theoretical investigation of the vibrations associated with a spherical cavity in an elastic medium was undertaken.

Jan 1, 1950

By C. -K. Fang, T. H. Chuang

"Temperature effects on the erosion of the 6063 aluminum alloy were investigated. Erosion experiments were performed by sandblasting silicon carbide particles of 80 grit size. The target volume loss, and worn depths of the eroded material were investigated at different temperatures. It was found that the temperature had only a minor impact on the peak attack angle. The effect of temperature on erosion damage depended on the relative humidity (RH) of the environment. IntroductionThe synergy of wind and sand or dust may result in the erosion of materials. However, the severity of erosion damage in different areas and in different seasons might be varied, depending on environmental variables such as temperature and humidity. As a result, determining the effect of environmental variables on erosion damage is important in selecting or ranking materials for their suitable applications in diverse areas.The relationship between erosion wastage and temperature is governed by many factors including temperature dependent properties of the material (strength, ductility, toughness, and dynamic hardness, etc.), mechanical erosion characteristics, the rate of oxidation, and the mechanical properties of oxides. Although the effect of temperature on erosion has been studied for engineering materials (Smeltzer et al., 1970; Gat and Tabakoff, 1978; 1980; Levy et al., 1986; Levy and Man, 1986; Chinnadurai and Bahadur, 1995; Howard and Ball, 1997; Colclough and Yeomans, 1997; Suckling and Allen, 1997), published literature dealing with aluminum alloy is rather limited."

Jan 1, 2000

By Charles Barrett

PLASTIC flow in metal crystals and the changes in orientation resulting from it are generally understood to take place by the following funda-mental mechanisms: (1) slip on crystallographic planes, (2) homogeneous crystal rotation resulting from the slip, (3) bending of the lattice between the planes of slip, and, under certain circumstances, (4) twinning. This paper and a preceding one on iron subjected to uniaxial compression1 concern two additional processes that must now be added to this list: (5) the formation of deformation bands, and (6) the bending and rotation of these bands. The present investigation yields a new understanding and definiteness to the common terms so loosely used when speaking of cold-worked metals -"grain fragmentation," "elongated grains," and "deformation twins," "deformation bands," "etch bands," or "X-bands." Bands have been noted on the polished and etched surfaces of cold-worked metals by vari-ous investigators for more than 25 years, ? yet their nature and their significance have been so little understood that they are not treated in the most comprehensive modern texts on the deformation of crystals. The experiments in this series show that they are one of the fundamental processes in the deformation of metals, of importance in the development of preferred orientations, in work-hardening (since they have the effect of reducing the effective grain size and interfering with slip), and in the recrystallization process. The present experiments were performed on the same stock of mate-rial that was used in the earlier compression experiments1-hydrogen-purified mild steel in which the carbon content had been reduced to the limit detectable under the microscope and in which single crystals could be grown by a strain-anneal treatment.2

Jan 1, 1939

By H. E. Sanford

"INTRODUCTION Of the occupations in and about coal mines, those of the haulage crews are among the most hazardous. Statistics indicate that the second largest number of fatalities about coal mines occurs during haulage operations and through the use or misuse of haulage equipment. Despite the fact that relatively few coal-mine employees are engaged continuously at haulage operations, approximately 20 percent of all coal-mine fatalities are attributable to haulage.Most of the hazards in haulage operations could be very greatly reduced if more serious consideration were given to the problems of the haulage crews and if sincere efforts were made to reduce the hazards. Underground haulage is similar in many respects to railroading; yet, railroading is now considered one of the safest of occupations a distinction that has been attained only by honest effort and whole-hearted cooperation on the part of all concerned. Underground haulage is also similar to street and highway operation and has in it some of the difficulties encountered in the reduction of traffic accidents the seriousness of which has not by any means been con¬trolled as yet, notwithstanding the fact that much effort has been expended through a multiplicity of laws, ordinance regulation, etc., as well as by thousands of enforcement agencies and officers.The men working on the locomotives are among the most important members of a coal-mine organization; without skilled haulage employees, the production of coal would be greatly retarded. Their jobs, particularly the job as brakeman, require physical endurance, agility, and mental and physical alertness; in thin coal beds, especially where the roof is not brushed and the coal is loaded into mine cars by hand, the need for these qualifications is greatly increased."

May 1, 1948

By Y. C. Liu

Ningxiang-type iron deposit is a most important sedimentary oolitic hematite deposit in China. Its? detected ore reserves are 3.72 billion tons, which is 73.5% of all detected reserves, and there are about 10 billion tons of prognostic resources. It is considered as the ?poor mine? for a long time be-cause of its difficult prooerty. But based on the ore characteristics of different deposits, the technological characteristics of ore are different with great diversity in ore baring horizon, distribution range, deposit scale, ore petrology, ore mineral assemblage and iron content. Through the study of deposit features and technological mineralogy of different Ningxiang-type of iron deposits in China, and based on industrial types and natural types of ore deposits, we divide different technological types according the technological features of the ore such as mineral composition, particle size, dissemination, occurrence of useful elements and harmful elements, the main physical and chemical properties of mineral and geological conditions of deposits, etc, moreover, propose the different utilization, mineral processing technologies and product schemes for the different types of ore.

Jan 1, 2014

By AIME AIME

AN enthusiastic crowd, cheerfully confident that the upturn in the oil industry has arrived, gathered in Los Angeles on Sept. 29 for a Petroleum Division meeting arranged by the Southern California Section. The assembly room of the California Oil and Gas Association was the place of meeting. H. Norton Johnson was in the chair for the morning session, with about eighty members and guests present. Four papers were presented before lunch and a fifth, on electrical coring, was withdrawn as the work on which it was based is still confidential. Joseph Jensen read his contribution on the "Kettleman Hills Middle Dome Unit Plan" and, as he had an active part in framing the plan, his outline and discussion of it was authoritative and informing. J. H. Woods asked concerning the operation of the casing-head gasolene plant under the plan and was informed that one company would operate the plant and royalties would be paid participating companies

Jan 1, 1933

By S. Z. Shafaei

An experimental investigation has been carried out using a laboratory scale Denver flotation cell. For evaluation of cokeable coal of Alborze Sharghi coal washing plant, the full factorial method was used to statistically design and analyse the experiments. The 2 factorial interaction model were developed for combustible recovery and ash content as response and diesel dosage, conditioning time, feed percent solids and rotor speed as factors. Model validation and residual analysis were con-ducted and results indicated that the fitness, predictability power and residual distributions of models were good. The effect of parameters and interactions were examined and it has been demonstrated that rotor speed, solid percent and interaction between diesel dosage and solid percent were more important terms of all responses. A product with approximately 78% combustible recovery and 10% ash content was obtained at 4000gr/ton diesel fuel oil (high level), 30 sec conditioning time (low level), feed percent solids of 15% (low level) and 800 rpm rotor speed in appropriate condition.

Jan 1, 2014

By H. Wilhelm, E. L. Davis, W. A. Clark

MATHEMATICAL formulas for the analysis of the behavior of producing oil wells can be devised which will be correct for the assumed conditions. However, in an oil zone, variables always exist which are unknown, or to which. it is impractical to assign mathematical values. It seems apparent that one should reason back from observed facts to an analysis of causes, rather than start with a hypothetical reservoir with assumed properties and attempt to explain observed phenomena. In this paper we hope to throw some additional light on factors influencing production, especially edgewater behavior. OIL and gas are contained in reservoirs of either the sealed type or the edgewater type. In the former all the recoverable oil is produced by gas expansion only. In this type of reservoir, edgewater is not effective. This may be because of faulting or overlapping strata, or more often, probably, the edgewater pressure is ineffec¬tive on account of resistance or lack of head.

Jan 1, 1933

By Charles H. Rich

This Bureau of Mines report is an expansion and update of Information Circular 8719 and comprises maps and tables listing the name, location, and other pertinent data concerning certain fuel-related projects. The maps show the locations of the planned or proposed facilities. The tables include information on projects involving the proposed or planned development of fuel resources, as well as the development of storage, transportation, and conversion facilities. The report covers the 24 States west of the Mississippi River including Alaska and Hawaii. Of the 808 projects for which information is provided, 219 concern coal mines, 246 concern electric generating plants, and 115 concern uranium mines; Energy Supply and Environmental Coordination Act coal conversion notices are also included. Because of the dynamic nature of the energy industry, many uncertainties exist and some of the listed projects may never become realities. Also, no attempt has been made to determine the degree of certainty or viability of each project.

Jan 1, 1978

By James Ruddy

THE medical program of the Climax Molybdenum Co. is under the supervision of the department of industrial medicine of the University of Colorado, of which James J. Waring, professor of medicine at the University Medical School, is director. Dr. Waring is consultant and direct supervisor of both the hospital and industrial medical department at Climax. At Climax the program is in charge of the medical director and the associate physician, Dr. Galen M. Hover. The hospital at Climax is completely equipped with all that is necessary for the practice of scientific medicine and surgery. Only graduate registered nurses with experience in industrial medicine are employed. Being only a few hundred yards from the portal of the mine. acci-

Jan 1, 1946

By A. Martikainen, S. GYAMFI

Luossavaara-Kiirunavaara Aktiebolag’s (LKAB) Konsuln iron ore mine, located just south of the famous Kiruna iron ore mine in Malmfälten in northern Sweden inside the Arctic Circle, was developed as a test mine between 2018 and 2020 for the Sustainable Underground Mining (SUM) project [1]. Besides functioning as a test mine, Konsuln also contributes to ore production. The existing mine ventilation system was designed for the current production rate of 0.8 Mtpa using conventional diesel machines. The design was created by Kiruna mine ventilation team, Stina Klemo and Joakim Jonasson, in cooperation with a consultant, Tomas Bolsöy from EOL Vent Mining AB. There is a plan to increase this rate to between 1.8 and 3 Mtpa in the future, and this requires the primary fans to be upgraded. Therefore, a study was carried out to determine whether using ventilation on demand (VOD) could avoid this fan upgrade and reduce Konsuln’s ventilation and heating power costs in the future. The study also investigated whether using battery electric vehicles (BEVs) along with VOD or as a standalone strategy could further reduce these power costs. In addition, the study analyzed the suitability of heating power reduction strategies presently or previously used in Nordic countries and Canada to investigate potential additional strategies to reduce heating power cost, the largest portion of Konsuln’s ventilation and heating power costs.

By G. L. Alston

Rigid urethane foam can be used effectively for improving mine air conditioning systems by reducing heat and moisture transfer from mine rock to ventilating air and from mine rock to ventilation ducts, for erecting mine ventilation stoppings and overcasts, for sealings around door frames and bulkheads to prevent air leakage, for preventing spalling and sloughing of roof and rib and for erecting fire-resistant powder magazines and transformer or compression stations. Rigid urethane foam is a tough, cellular material, made by nixing diisocyanate and polyether polyol resin in accurate proportions through an applicator system, then the two chemicals react, the mixture expands thirty times its original volume with 85 to 95 percent closed cells. Within seconds, the mixture solidifies and takes a preset which will adhere to overhead or vertical surfaces. It will adhere to brattice cloth, steel, wood, concrete and rock, Excessive wetness will reduce the adherence, but in such cases adherence can be improved by preliminary application of an absorbent dust such as cement.

Jan 1, 1963

By AIME AIME

AT Williams College, in the quaint old New England town where people still go to the post office for their mail, an interesting institution has come into being as one of the aftermaths of the peace conference at Paris in 1919. The war taught the world many things about economics although much remains to be learned and more to be appreciated. B. M. Baruch, H. A. Garfield, president of Williams, and others who took part in the conference at Paris or in preparation for it, feeling that benefits would accrue from informal friendly discussion of the problems that lead to political differences between peoples, called together a summer conference in 1920. This has now become an annual affair and is coming to be looked upon as an important center for developing and stimulating public opinion. Membership in the Institute is by invitation and the lists change to correspond with the particular subjects taken up. Each year a number of distinguished foreign public men are invited to be the guests of the Institute and to meet men and women from various parts of the United States interested in their special subjects. Round tables, general conferences, and public lectures are the means employed to bring out discussion. The first are organized by groups, each including usually 25 to 40 people interested in a special subject and meeting three times a week for informal discussion. Teachers, writers, economists, engineers, business men, indeed men of all vocations and many shades of opinion, are brought together. Once a week each round table presents in general conference with the members of all other groups the more general conclusions reached in its own decisions. Afternoon and evening lectures are given by the foreign guests and these are open to the public. The lectures and the general conferences are reported widely in the press but the proceedings as a whole are not printed, no resolutions are passed, and no action is taken or contemplated. The whole plan is to furnish a forum for free discussion in hopes that the difficulties of various groups and peoples may be taken up sympathetically and good understanding promoted. There is no creed, doctrine or dogma to which the Institute is committed and widely different views are currently presented. The constant effort is to bring out points of view and the reasons for them rather than to build up convincing arguments favourable to a specific action

Jan 1, 1926

By Sidney Katell

An economic analysis of underground gasification of coal, based on experimental results obtained by the Bureau of Mines, indicates that a gas suitable for use in a power plant might be produced for approximately $.62 to $.77 per million British thermal units. This estimate does not include cost of land purchase. The gasification experiments were conducted in a 3-ft. seam of high volatile A bituminous coal. The major factors which can influence a change in operating costs are height of overburden, power costs, thermal efficiency, and the gasification air inlet pressure. The following equations show the relationship of these factors to operating costs:

Jan 1, 1961

By X. Wang, Y. Luo

The propensity of coal spontaneous combustion can be evaluated using various laboratory testing methods, such as R70 adiabatic tests, thermal gravimetric analyzer (TGA) tests and critical self-heating temperature (CSHT) methods. Each of the methods has its unique characteristics and index for classifying the propensity of self-ignition of coals. Accountable relationships among the propensity indices of different methods should be established. Using the newly established R70 and TGA testing setups in our ventilation laboratory, samples from U.S. coal mines have been collected and tested. The TGA is a relatively new quantitative method. A test can be conducted in a relatively short time, within about one and a half hours, compared to the adiabatic tests. The temperature and weight of the sample can be measured with high precision and then used to determine the activation energy of the coal, which is a good indicator of the potential for self-heating. Under a specific experimental design, the TGA technique could perform the proximate analysis for determining coal quality parameters (e.g., moisture, volatile matter, fixed carbon and ash content). These parameters can be used in an empirical equation for assessing the potential for coal self-ignition. The trend of activation energies determined using TGA techniques is reasonably consistent with the trend of activation energies determined using adiabatic tests. As a case study, a comparative analysis of these two methods for determining activation energy was made on coal samples collected from Indiana. The kinetics of the spontaneous combustion mechanism has been explained. If the functional groups of a coal such as hydroxyl (-OH), carboxyl (-COOH), methyl (-CH3), etc., activate more easily with a small amount of activation energy at a relatively low temperature, the coal will have a higher potential for self-heating. With the kinetic and coal quality parameters determined by the TGA setup, it has been found that the coal with a low potential for self-ignition has low self-heating rate, a high activation energy and a high minimum self-heating temperature.

Jan 1, 2012

By Thomas T., Read

TWO American students entered the Ecole des Mines in 1856, Joseph Lesley of Philadelphia and Thomas Egleston of New York. Lesley remained there only one year, but Egleston completed the whole 'curriculum and received, in 1860, the certificate given to foreign students .in lieu of the official appointment and degree. awarded French students. Returning home he received, in 1861, an appointment by Secretary Henry of the Smithsonian Institution to sort, label, and arrange the collections of mineralogical and geological specimens which had been brought to Washington by the various government exploring expeditions in the West. Thomas Egleston, born in New York City on Dec. 9, 1832, was the son of Thomas Jefferson Egleston, who came to New York from Massachusetts some time before 1829. The first American ancestor of the family had settled near Dorchester. in 1630. T. J. Egleston and Joseph Battell established an iron-merchandizing business* at 166 South St., New, York, which prospered exceedingly; so much so that when Thomas J. Egleston died, July 12, 1861, his estate had a book value of over $500,000. Since an older brother was expected eventually to take over this business, Thomas, who had a liking for science, went to Yale,, where he completed the regular four-year course in 1854, and then remained another year for advanced work in chemistry under Silliman. I One biographer says he went to Europe, . early in 1-856, on account of his health. It was the custom at that time for wealthy young men to make a tour of Europe after completing their academic education. Whatever the precise reason, he began scientific work at the Jardin des Plantes in Paris but soon trans* It still operating as Egleston Bros. Inc., though no direct descendants of its founder are now living.

Jan 1, 1941

By Harry Freund, Kenneth H. Hammill, Francis C. Bissonnette

"Gallic acid is a sensitive, stable, colorimetric reagent for the determination of tantalum in the range of 2 to 40 µ g.Ta/ml. The method consists of the fusion of tantalum oxide with potassium pyrosulfate and solution of the cooled melt in saturated ammonium oxalate, followed by development of a yellow complex with an ethanolic solution of gallic acid. The tantalum-gallic acid complex absorbs over a broad region in the blue and near ultraviolet. Adverse effects due to interfering ions and solution conditions, such as oxalate concentration and pH, can be minimized by a suitable choice of wave length.by a suitable choice of wave length.A new and sensitive colorimetric method is provided that has been used successfully at the Northwest Electrodevelopment Laboratory of the Federal Bureau of Mines for determining minor amounts of tantalum.INTRODUCTIONThe development of corrosion-resistant alloys at the Northwest Electrodevelopment Laboratory prompted a review of the analytical chemistry of columbium (niobium) and tantahnn. Not only are these elements difficult to determine in small amounts, but tantalum especially lacks both sensitive and characteristic color reactions. Various phenolic compounds have been suggested as colorimetric reagents for tantalum, Quentin and Wagner (10, p. 24B) 1/ recommend the use of tannin. The use of pyrogallol was suggested originally by Krivoshlykov (6, pp. 59-60), whose method recently has been subject to a number of modifications (3, pp. 249-254; 5, pp. 1340-1344; 1, pp. 1803-18oi; 4, pp. 345-350). The yellow coloration produced by pyrocatechol in an oxalate solution containing tantalum may also be used to estimate tantalum ( 11, pp, ll-1-4-148) . The use of hydrogen peroxide has been recommended also (7, pp. 164-165; 9, pp. 926-931).Aside from a lack of specificity and sensitivity, the major failing of phenolic reagents is their susceptibility to air oxidation. The oxidation products are highly colored and absorb in the same spectral region as the tantalum complex. Holding reductants are not completely satisfactory in minimizing this effect. Increasing the acidity, while retarding the oxidation, has an adverse effect on the tantalum sensitivity."

Sep 1, 1956

By C Haughy, F F. Pitard

Blue Mountain Minerals is a large supplier of calcium carbonate products used by various manufacturers as a major raw material. Very small amounts of free carbon in the rock can have a huge impact in carbon-sensitive applications. The marble in the deposit at Blue Mountain Minerals contains variable amounts of free carbon in the form of trace amounts of the mineral graphite.To make quality improvements, variography was used to measure the impact of non-ideal sampling practices at the Blue Mountain Minerals operations in Columbia, California in the United States. A major investment in correct sampling systems and sampling protocols was implemented over a one-year period. Subsequent variography was used to measure the improvement on the predictability of the graphite content in marble produced by the quarry and as it is processed as an acceptable raw material for extremely carbon-sensitive applications. The improvements of the sampling protocols, control of long-range changes and better knowledge of process cycles are easily noticeable on variograms when they happen to exist. The economic impacts are discussed.CITATION:Haughy, C and Pitard, F F, 2017. Use of variography to measure improvement of sampling practices for the quality control of graphite consistency in marble used for carbon-sensitive applications, in Proceedings Eighth World Conference on Sampling and Blending , pp 255–260 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017