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By D. J. Donaven, Manuel Gomez, W. S. Landers

Bulk density tests were made on a Western U.S. coke oven plant blend to obtain bulk density control data that would be directly transferable to plant practice . Maximum bulk density values were obtained at zero surface moisture . Increase in surface moisture to about 6 percent decreased the bulk density to a minimum value . Increase in the fine grinding of the blend , at constant surface moisture , decreased the bulk density . The effect of oil on bulk density was observed with five oils at concentrations ranging from 1/8 to 1-1 / 2 gallons per ton . Maximum bulk densities were obtained within the 1 / 2- to 1 - gallon - per - ton range . Essentially the same bulk densities were obtained with petrolatum- and nonpetrolatum- containing oils . Storage effects were observed on samples tested at selected intervals from 0 to 56 days . No significant change in bulk density took place if no surface moisture was lost during storage .

Jan 1, 1964

By Thomas O. Llewellyn

This U.S. Bureau of Mines (US8M) report presents a concise review on sources, processes, supply, and historical use patterns of domestic cadmium. It also covers a preliminary estimated cadmium material balance for the year 1989.

Jan 1, 1992

By G. Richards Gwinn

The mineral olivine, though known to mineralogists for many years, was of little commercial value in the United States before 1933. It was first described in 1790 by Johann Gottlieb Werner, who named it "olivine in allusion to its olive-green color. Commercial olivine first attracted attention because of its refractory properties. Further research has developed methods of extracting the magnesia content for the production of various magnesium compounds. Experimental and pilot-plant work also are in progress to make olivine available as a low-cost raw material for the production of magnesium metal.

Jan 1, 1943

By R. Karl Zipf

A fatal explosion in a sealed area at the Sago Mine in 2006 prompted researchers and regulators in the United States to re-examine the requirements for explosion-resistant mine seals. Seals are used in underground coal mines to isolate abandoned mining areas from active workings. Prior to the Sago disaster, mining regulations required seals to withstand a 140 kPa explosion pressure. Recent research at the National Institute for Occupational Safety and Health (NIOSH)Pittsburgh Research Laboratory showed that pressures from explosions can far exceed this pressure. U.S. mining regulations now require much stronger seals. Current research focuses on understanding the science, engineering and management of sealed areas of coal mines. Scientific efforts seek understanding of how explosive methane-air mixtures accumulate using measurements and models of the sealed area atmosphere. Additional scientific efforts aim to understand the explosion pressures that can develop using a combination of numerical modeling and experiments. Engineering efforts aim to produce design guidelines for seals that can resist the new higher pressure design criteria. NIOSH researchers are also developing guidance for monitoring of sealed area atmospheres and inertization of potentially explosive gas mixtures within sealed areas. This paper seeks to encourage scientific discussion among international peers since preventing explosions within sealed areas is of interest to underground coal operators and regulators.

Jan 1, 2009

By S. J. Aresco

The Bureau of Mines has been active in promoting the purchase of coal for Government use under specifications that define the requirements in terms of heating value of the coal, expressed in British thermal units, and the composition as shown by proximate analyses. To these, when required, are added the ash-softening temperature, the free-swelling index, and the Hardgrove grindability index. Under most of these specification contracts the bidders guarantee the quality of the coal, and that guaranteed by the successful bidder becomes the standard of his contract. The deliveries are sampled in accordance with instructions4/ issued by the Bureau of Mines; the samples are analyzed in the Bureau laboratory to determine whether the coal is of the quality guaranteed by the contractor and, if it is not, a price adjustment is made. Analyses of the delivered coal and tipple samples (samples collected at mine tipples as coal is being loaded into railroad cars or trucks) provide valuable data for use in evaluating future bids. In addition, the continuous .sampling of coal as delivered is a check on the practical results obtained in burning the coal.

Jan 1, 1958

By J. W. Miller

This report deals with upgrading of the coal reserves of Raleigh County, VI. Va., to metallurgical standards. The data on samples herein correctly show the characteristics of the bed at the point where sampled and are used to indicate the general quality of the bed in the county. The principal results and conclusions are: 1. Raleigh County contains large reserves of high-quality, high-, medium-, and low-volatile coals. 2. The principal beds from which an increased amount of coal is expected to be mined in the future are: The Eagle, Powellton, No. 5 Block, Hernshaw, Fire Creek, and Pocahontas No.6.

Jan 1, 1954

By E. C. Lane

"INTRODUCTION The first important discovery of petroleum in New Mexico was near Dayton, Eddy County, where the Brown well was drilled in 1909, and small quantities of oil were produced. In 1911 and 1912 wells were drilled in McKinley County, but commercial production did not begin until the discovery of the Hogback field, San Juan County, in 1922. The discovery well in the Artesia field, Eddy County, drilled in 1923, gave impetus to active drilling in many areas. Since 1924 New Mexico has produced petroleum in commercial quantities and since 1930 the State has joined the ranks of the big produc¬ing States, being sixth or seventh in total production in recent years.Production by years. 1924 to 1940, inclusive, taken from annual figures in Bureau of Mines Minerals Yearbook, are given in table 1. The total production shown is 274,331,000 barrels. Andreas 3/ has published production figures for the year 1940 and a resume of all production to the end of 1940. Data from his report are presented in table 2 for each field sampled. The cumulative production, as given by Andreas, is 270,618,575 barrels."

Aug 1, 1942

By Arthur L. Murray

"Oil-shale camps are peculiarly favored, in that before they are established it can be ascertained with a,of certainty, that the life of the project is not limited. Unlike camps at metal mines, where the metal content of a given area is frequently an unknown quantity until after years of development, oil-shale camps should, from the outset, be planned and built as permanent types of camps. Where this procedure is followed camps will be established which better serve the needs of the industry and the cost of their general care and upkeep will be less.Selection of camp or townsite.The site of the camp or town, whether on company property or not, should be selected with care. It should be separate if possible from the location of the plants of the company so as to be free from noise and fumes and so as to provide a change of environment for employees in going from their work to their homes.The principal features governing the site to be selected are as follows:Drainage. The general contour of the surrounding country should be such that drainage is away from the site. The camp or town should, if practical, be situated on higher ground than that in its immediate vicinity.Soil. The nature of the soil on which the camp or town is located may bear a decided relation to health. A porous, well under drained top soil of at least four feet in depth insures dryness and facilities the placing of foundations and the laying of water mains and sewer pipes. Such a soil also is an advantage in growing trees, shrubs and grass plots, which are a decided adjunct to making the community attractive."

Jun 1, 1921

By H. W. St. Clair

This study of the rate of evaporation of zinc was undertaken as a part, of a general investigation on refining mixtures of metals resulting from melting reclaimed scrap. One of the methods by which the more volatile metals, such as zinc, magnesium, and cadmium, may be separated is by distillation. Distillation may be carried out at lower temperatures if it is done in an evacuated enclosure. The immediate purpose of the present investigation was to determine accurately the effect of temperature, pressure, and other factors on the rate of evaporation of zinc.

Jan 1, 1950

By Walter W. Fowkes

Leonardite is a coallike substance, similar in structure and composition to lignitic coal and believed to be derived from lignitic coal by the process of natural oxidation. Leonardite is little known outside lignite-producing areas and has been developed commercially only to a minor extent. The higher oxygen content and less compact structure of leonardite, compared with lignite, make it undesirable as a fuel but indicate that it has potential as a source of chemicals and for other nonfuel uses. It is a convenient source of humic acids. The United States has a large natural reserve of leonardite; furthermore, it can be produced in the laboratory under controlled conditions. The significant elemental difference between leonardite and lignite is the oxygen content (leonardite, 28-29 percent; lignite, 19-20 percent). The higher oxygen content of leonardite is due entirely to a Larger number of carboxylic acid groups. This fact explains the 17-Cold increase in alkali solubility of leonardite. Spectral studies indicate that the material is mixed salts of humic acids.

Jan 1, 1960

By J. Mutmansky, C. Lee

"The size distribution of coal mine dust is one of its most important characteristics because the particle size is known to govern the region of deposition of dust within the human respiratory tract. In addition, dust characteristics, particle settling rate, transportability of the dust and the efficiency of dust control measures are all affected by the particle size. As a result, particle size distribution of the airborne dust in a coal mine is a fundamental property that impacts on the health of underground workers.This paper deals with some basic findings on the size distribution of cool mine dust based upon the results of data collection in six underground coal mines using continuous miners. All airborne dust sampling was performed on development sections using eight stage cascade impactors and permissible 2. O l / min pumps. Samplers locations were fixed in the sections with respect to the continuous miner and roofbolter or with respect to the intake and return airways • Sampling times varied from 45 minutes to 6 hours , depending upon the dust concentration. The first topic of analysis was the test to determine whether the commonly used lognonnal distribution is valid when applied to airborne coal mine dust. Secondly, the conventional method of representing the· distribution using two parameters, the geometric mean and the geometric standard deviation, is questioned. Since almost all size data were found to show some degree of bimodality, the two parameter lognonnal distribution may not represent the total airborne coal mine dust size , quite adequately. Bimodal lognonnal distribution was tested to be a good approximation in the case with two modes in the size distribution.The final topic discussed in this paper is the 'locational variation of the airborne dust size distributions within the continuous mining section. The size distributions varied considerably at the different sampling locations with the continuous miner and roofbolter producing the coarser distributions. Fine size modes in the range of 2 to 4µ m including mostly respirable dust particles were present in almost all samples • Second dust generating sources such as the shuttle car movement were found to be major causes of high respirable dust concentrations in some cases ."

Jan 1, 1988

By Carlton E. Brown

This report contains information on the relation between and precision or reproducibility of counts (light-and dark-field) of the dust in liquid from simultaneous impinger, midget-impinger, electric-precipitator, and filter-paper samples. The impinger was the main sampler used from about 1922 to 1939 by industrial hygienists in the United States for collecting samples of unhygienic dust from the atmospheric environment of workers. The midget-impinger, a small modification of the preceding impinger described in 1937, has been the sampler used most since about 1939. Electric precipitators5/6/ have been used to a limited extent, mainly by the Bureau of Mines in the laboratory, for obtaining results comparable to impinger results. A filter-paper sampler for obtaining results comparable to impinger results has been described by Brown. All these samplers have a high collecting efficiency for particles larger than 1 micron in diameter revealed by the usual light-field counting procedure. However, their collecting efficiencies are quite variable for the smaller particles revealed by the dark-field counting procedure used in this study. Published information on the relation between the results of these samplers is limited and scattered. Summaries of some of this information are given in this report along with some previously unpublished information.

Jan 1, 1949

By M. D. Aldridge

The results of a four-year research effort aimed at developing a practical and effective electronic system for monitoring safety conditions throughout a coal mine by displaying, at a central location, remotely measured parameters are described. This document presents the general philosophy of an experimental system in an operating coal mine. The conclusions drawn from this experience are presented and a typical design for a large coal mine is described.

Jan 1, 1974

By David J. Kusler

This report describes a primary or direct, continuously sampling, and automatically averaging gravimetric method for analyzing gaseous mixtures of carbon dioxide, carbon monoxide) hydrogen, and (by volume measurement) nitrogen. The gaseous mixture is analyzed by passing it at a controlled and definite rate through a system that permits carbon dioxide and water retained by appropriate absorbents to be determined and the residual-gas volume (essentially nitrogen) to be measured. The accuracy and dependability have been established by comparison with very carefully conducted Orsat analyses. The method was developed for, and has been satisfactorily applied to, the analysis of blast-furnace top gas. It permits relatively attention free operation, using simple and low-cost materials usually found as basic equipment in the analytical laboratory. It provides, over a wide range of time or sampling intervals (from less than 1 to over 24 hours), the average composition, in terms of volume-percent, for those components usually determined in blast-furnace gas, if (as is usual) the flow rate of gas from the blast furnace is essentially constant over a selected analysis interval. Oxygen and methane are not determined; but, since these gases are normally absent or present only in traces, their analysis is seldom required.

Jan 1, 1959

By C. C. Blade

"This report on the properties of motor fuels sold through service stations ni the Unietd States is a continuation of a series of reports made in accordance with a cooperating agreement between the Coordinating Fuel Research (CRF) Committee of the Coordinating Research Council (CRC)3/ and the Bureau of Mines of the United States Department of the Interior. The first of these reports presented data on motor gasolines sold during the winter of 1935-36.4/ Further reports were issued describing motor gasolines sold during the succeeding summers and winters to and including the summer of 1941.4/ No reports were made on motor gasolines sold during the winter of 1941-42 and during the summer of 1942. However, starting with the winter of 1942-43, the semiannual reports were resumed.4/The present report presents analytical data for 1,381 samples, representing the products of approximately 75 companies. Most of the samples represented in this report were secured during July and the first half of August, 1945. As in previous surveys, the companies covered by the survey include both large and small suppliers. Conforming to former reports, the data cover three groups of samples – regular-price, premium-price, and third-grade gasolines.As the number of analyses submitted for samples of third-grade gasoline are not considered adequate to represent this type of motor fuel, data for the analyses have not been averaged, but the individual items are tabulated. The number of samples, items and brands comprising each group is as follows: Regular-price, 733 samples, 229 items, and 57 brands; premium-price, 504 samples, 197 items, and 56 brands; third-grade, 84 samples, 28 items and 12 brands. The meanings of these terms as sued in the surveys are as follows:"

Jan 1, 1946

By P. G. Barnard

The Bureau of Mines investigated the effects of various additions of rare-earth metals or rare-earth oxides on the mechanical properties of cast and wrought plain-carbon steels. Rare-earth metals, as misch metal, were added to medium-carbon steel in amounts to 0.70 weight-percent; rare-earth oxides, as a commercial mixture, were added in amounts to 1.50 weight-percent. The melting and casting of conditioned steels were done in a vacuum-induction furnace, to avoid formation of oxides from the melting atmosphere and to pro-vide better control over chemical composition. At room temperature, data for tensile strength, yield strength, elongation, and hardness of cast and wrought steels were obtained by standard testing equipment and procedures. Impact tests were conducted on as-cast steel specimens. The greatest amount of tensile ductility and impact strength was obtained in as-cast steel with 0.50 to 0.70 weight-percent misch metal additions. No significant improvement on mechanical properties was indicated in wrought steels containing rare-earth metal additions in the range from 0.10 to 0.70 weight-percent. In general, the rare-earth oxide additions up to 1.50 weight-percent had little effect on the tensile properties of steel in the cast, wrought and annealed, or wrought and normalized condition.

Jan 1, 1967

By H. H. Schrenk, L. B. Berger, W. P. Yant, F. A. Patty

"The use of small such as canaries and white mice, for detecting carbon monoxide depends primarily on the fact that the volume of respiration of these animals in proportion to their volume of blood is much higher than for man. Accordingly, when animals and men are simultaneously exposed to a given concentration of carbon monoxide the animals will absorb it more rapidly and attain serious poisoning in less time than men. Prom a practical viewpoint the use of the animals depends on the margin of time between observable symptoms in them and serious poisoning in man, during which man can return to fresh air or use respiratory protection. It should be remembered, however, that during the time the animal is incurring a detectable degree of poisoning, man is also absorbing some carbon monoxide, and the margin of time is not very wide. Experience with canaries has shown that an occasional specimen may have a tolerance above the average of the species and fail to exhibit symptoms before man incurs a very discomforting and possibly a serious degree of poisoning.It is also well known that physical activity increases the demand for oxygen by the body, and the respiratory exchange and circulation of the blood are increased to meet the demand. This sets up a vicious condition if carbon monoxide is present in the air because the rate of absorption of carbon monoxide is not only increased by the increase in respiration and circulation, but the absorption of carbon monoxide decreases the capacity of the blood for carrying oxygen at a time when the demand is high. These facts, together with the increase in respiration and circulation which attend excitement, underlie the caution to be calm and to walk slowly and to reduce physical exertion to a minimum when exposed to carbon monoxide. For these same reasons, when using animals for detecting carbon monoxide it is endeavored to keep them active, thereby tending to increase the response of the birds and widen the time between observable effects in the birds and effects in the man. As rule canaries are kept fairly active through fright at the unnatural surroundings and in their endeavor to remain on the perch of the cage when carried into the atmosphere to be examined. They also experience an excitement stage with oncoming carbon monoxide poisoning. Sometimes, however, especially if the air is cold, they tend to be inactive and quiet. Ordinary mice and white mice become inactive with use and also with oncoming poisoning. They huddle in the corner or the cage, and thereby not only reduce their sensitivity but make it difficult to observe signs of poisoning."

Oct 1, 1930

By M. H. Kline

The Scarlet mine, in Randolph County, N. C., was operated on a small scale at intervals from 1899 to 1915, but no records of the quantity of ore produced are available. J. I. Moore unwatered the mine in March 1948, and Bureau of Mines' engineers examined the underground workings. Several assays checked previous sampling of the mine and indicated a small but comparatively high-grade copper-zinc deposit. The high metal content of the veins and the possibility of developing additional reserves prompted the Bureau of-Mines to drill three holes, totaling 530 feet, at the deposit during March and April 1948. Drilling disclosed that the mineralized vein did not extend over 300 feet along the strike and is probably limited in depth to the contact with the granite mylonite.

Jan 1, 1949

By T. L. Marchewka

As part of its program to conserve the Nation's natural resources by developing improved performance materials, the Bureau of Mines, U.S. Department of the Interior, in cooperation with the U.S. Department of Energy, has conducted an investigation of materials of construction able to withstand the high temperature and hostile environments encountered in coal gasification units. Refractory pipe liners are required when extremely hot gases or abrasive solids are transported between processing units in the gasification plants. One promising technique for producing refractory pipe (or refractory pipe liners) is centrifugal casting. For this study, the effect of processing variables such as workability, additives, reinforcement and spinning time, and centrifugal force were evaluated using four commercial refractory concretes. In addition, data on characteristics such as strength, density, abrasion, and spalling resistance of 5-inch-diam refractory pipe were developed. Techniques for forming large-diameter (19-inch) refractory pipe also were evaluated. The test results indicated that all four refractory concretes could be made into strong, homogeneous pipe, but that optimum casting parameters had to be determined for each specific composition. The investigation revealed that the major controlling factor in the production of the centrifugally cast pipe was the workability of the refractory concrete.

Jan 1, 1979

By F. E. Joyce

The Bureau of Mines studied copper-nickel minerals (mainly sulfides) of the Duluth Gabbro Complex in north-eastern Minnesota to determine their response to selective high-temperature sulfatization techniques. The gabbro, containing 0.44 percent copper and 0.13 percent nickel, was ground to minus 325 mesh and sulfatized in a heated, rotating, stainless steel bench-scale retort. Tests demonstrated that over 95 percent of the copper and 80 percent of the nickel can be converted to water-soluble sulfates, depending upon the roasting conditions employed. Yield equations were developed using regression analysis for predicting the extraction of copper and nickel between the temperature limits of 520° to 670° C, the roasting time limits of 3 to 7 hours, and S02 limits of 10 to 40 percent in S02-air mixtures.

Jan 1, 1971