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The value of U.S. mineral raw material output reached a record $63.1 billion in 1975. This high exceeded the 1974 value of $55.2 billion by 14 percent. Among the three major mineral categories -fuels, metals, and nonmetals -only fuels showed an increase in value. Both the metal and nonmetal categories showed declines in value. The significance of this nearly $63 billion mineral output can be noted in the fact that it is the basis for the subsequent production of over $270 billion a year in energy and processed materials. Of the 78 individual mineral commodities included in these 1975 totals, only 17 registered gains in output, while 45 registered value increases, reflecting higher prices.

Jan 1, 1976

By Daniel E. Sullivan

This Bureau of Mines publication examines the potential impact on minerals of the tariff and nontariff agreements that resulted from the Tokyo Round of the Multilateral Trade Negotiations, which were conducted under the auspices of the General Agreement on Tariffs and Trade. These agreements will affect minerals by reducing tariff levels and by changing rules by which they are traded internationally.

Jan 1, 1981

By M. A. Trevits

During the time period from 1990-2007, 1601 reportable fires occurred in the U.S. mining industry (an average of 89 fires per year). The leading causes of U.S. mine fires were flame cutting and welding operations, frictional heating and ignitions, electrical shorts, mobile equipment malfunctions, and spontaneous combustion. The fact that mine fires continue to occur with an alarming regularity reinforces the importance of recognizing and eliminating the potential hazards and the overall need for improved fire control and suppression technology to ensure the best possible outcome during a mine fire. The National Institute for Occupational Safety and Health (NIOSH) is conducting an evolving comprehensive program of research that is addressing mine fire prevention, detection, management and suppression. This paper presents a summary of recent research accomplishments and provides an overview of the next phase of the NIOSH mine fire research program.

Jan 1, 2008

This report describes the development, installation and performance of a lonpwall illumination system. The longwall illumination system was installed at the Greenwich Collieries 112, Cockport, Pa. It utilized flourescent luminaires, intrinsically safe power distribution and is the first longwall system installed in Pennsylvania.

Jan 1, 1976

By R. H. Harrison, D. R. Douslin

The thermodynamic properties H - H° , (H - H° ) /T , S - Sideal , S - S° Fide al F - F° , (F F° ) /T , and activity coefficient Y for perfluorocyclobutane were calculated as functions of temperatures ( 115.22 ° to 350 ° C) and molal density (0.75 to 6.5 moles / liter ) . Improved analytical and graphical correlating techniques are described .

Jan 1, 1964

By H. F. Yancey

A relatively large proportion of the coal produced in the state or Washington, especially in the coking coal areas is of fine size; hence washing by means of coal-washing tables to reduce the ash content is commonly practiced. For this reason the program of research in coal washing conducted jointly by the U. S. Bureau of mines and the College of Mines, University of Washington, has given special attention to the mechanism of the separation of coal from its impurities as affected by the coal-washing table with the object of

Jan 1, 1931

By E. H. Denny

"Reduction of mine accidents appears to depend upon essentially the same fundamentals, whether considered from the viewpoint of the mine operator, miner, State mine inspector, or safety engineer. Conditions of mine operation with respect to safety are governed in most States by a mining law, usually somewhat general in its provisions but more specific than laws dealing with other industries, Methods of mining development and practice evolved through experience have been handed down from generation to generation; many of these are intended to avoid injury to men and also loss of property. To carry out the intent of these bases of law and experience relating to safety supplemental measures and conditions are necessary. Among these may be: (1) Planned safety rules adapted to the mine and compliance by both officials and Miners with such of these rules as pertain to their work; (2) a supervisory force adequate and competent to ¬administer the mining laws and safety rules; (3) discipline adequate to secure compliance with safety measures; (4) safeguards against mechanical, electrical, falling, and other hazards; (5) mining operations planned with respect to safety of workers; (6) an active safety organization of officials and employees; (7) education of officials and employees in safety practices; and (8) an active sustained interest in safety by management and employees.This paper presents the viewpoint of the safety engineer, though a safety engineer connected with a specific mine or group of mines would be in a better position than the writer to present the industrial engineer's thought. The application of the mine safety fundamentals just outlined will be given consideration from observations of methods used by safety engineers and supervisors.The term ""safety engineer"" includes men of various duties, various degrees of experience, and various authority. Depending upon the size of the operation or the interest of the management in safety, the safety engineer may have accident prevention as his sole duty; he may be the head of a sizable safety organization; or he may be in part a claim agent; a statistician compiling figures for the enlightenment of the company, the public, or a mining institute meeting; a surveyor who must convince the miner that his scale of 10/10 equals 1 foot does not defraud the miner of 6 inches to every yard measured; or he may be by heaven¬ly gift an orator capable of assuring the employees that ""all's right with the world""; he may be a young engineer gaining, experience while checking the observance of company rules and investigating accidents; or he may have the physical ills frequently resulting from several decades of mining experience and instead of a pension, the position of safety engineer has fallen to his lot. He may have mine-operating authority to correct immediately a dangerous condition or practice or he may have his recommendations officially disregarded at the monthly meeting or when the bottom of the desk basket is reached. He is likely to find that his viewpoint on accident reduction is considered unsound today because of youth and inexperience and unsound later because of old age and senility. He is likely to find the easiest course to be that of attributing to Providence and the carelessness of the worker the mishaps that result in the removal of a man to the hospital or the morgue."

Dec 1, 1936

By Milton H. Fies

To present some idea as to how the Bureau of Mines may most effectively serve mining, it is necessary that we make some resume of its pact accomplishments in order to determine what, if any, changes will be of greatest service to the industry and to the nation. There are a great many times in life when one begins to wonder whether or not Emerson, in his famous epigram about "mousetraps" and "beaten paths" and "final recognition of intrinsic worth", took into account the item of time. The intrinsic value of any movement, of any work, of any accomplishment will ultimately be recognized, of that there is no doubt, but may a man in history has gone to his end in martyrdom because the world was slow in the acknowledgement of the true excellence of his worth, and this is likewise true of institutions.

Jan 1, 1934

By A. C. Richardson

The mine of the Porter Coal Co. is located at the town of Porter in the northwestern part of Jefferson, County, Ala., about 20 miles west of Birmingham. The operations in this mine are confined to the middle and bottom benches of the Mary Lee bed. The coal from the Porter mine is handpicked and washed before being placed on the market. The handpicked lump coal and the washed egg and nut, coal are sold chiefly as domestic and steam-raising fuel. The coal finer than 1 inch is washed in 2-compartment jigs and utilized in the manufacture of metallurgical coke. The coal company has found that, when coal ranging in size from 1 to 0 inch is washed in jigs, a considerable amount of high-ash material finer than 3/16 inch remains in the washed coal. This paper gives the results of an investigation which was conducted for the purpose of determining the washing characteristics of the through 316-inch raw coal and the extent to which the ash might be reduced by means of coal-washing tables. This investigation has been made in connection with an. extensive study of the coal-washing problems now being conducted by the United States Bureau of Mines and the University of Alabama, with the cooperation of the coal-mining companies of the State.

Jan 1, 1933

By Gerald T. Homce

Data from the U.S. Bureau of Labor Statistics show that 89 water well drillers died on the job between 1992 and 2002, and 28 of these deaths were electrocutions (Figure 1). In fact, elec­trical accidents are the leading on-the-job killer of water well drillers. The use of electricity is such an integral part of our lives that we usually take it for granted, but if we don?t understand or choose to ignore the hazards associated with electricity, the results can be deadly. Why is electrical shock so dangerous? If the voltage (of a shock) is sufficient to drive electrical current through your body, just 10 milliamps of cur­rent (1000 milliamps = 1 amp) can cause muscles to contract and prevent you from releasing an energized wire or tool in your grip. As little as 30 milliamps of current can paralyze your breathing, and 75 milli­amps can cause your heart to stop pumping blood (ventricular fibrillation). As a comparison, a small bedroom night-light draws about 30 to 60 milliamps. Other factors influence how severely you?ll be shocked if you touch a live electrical circuit, such as the path electrical current takes through your body and how long it flows, as well as your body weight. How much voltage is needed to drive electrical cur­rent through your body? Not much! Generally, any power source at 50 volts AC or higher is considered dangerous.

Jan 1, 2008

By Wendell L. Reich

Percussion drilling dates back to the hand operated star drill and hammer. Eventually steam and compressed air were substituted for muscle power and the mechanical percussion drill was born. From the hand held jack hammers, driving a forged steel bit into the rock, there evolved the jack leg, the rubber tired and crawler mounted drill carrier with automatic feed, increasing power and reducing man?s muscle requirements. Because the reaction of a blow on one end of a piece of steel has to be transmitted to the other end there is a limit to the depth or length of drill steel that can economically be used in out of the hole percussion devices. During the late 1800?s there is evidence that designers were attempting to put the percussion tool at the bottom of the hole, directly on the bit, in order to avoid the long drill steel which absorbed much of the blow, leaving little to be applied to the bit and the rock being drilled.

Jan 1, 1972

By G. L. Oldright

In the first Report of Investigations of the present series?(No. 4562) the usual course of progress ill reducing the minerals of low-grade ores to their valuable metallic components had been noted as advancing along two lines to concentrate a usually diminishing percentage of these minerals to a smaller bulk of richer product, and then to smelt the smaller bulk more cheaply per pound of metal produced. Fundamental properties of lead compounds made it difficult to treat much richer lead products than are treated at present in several steps of conventional lead smelting, unless ?marked modifications were made. No limits to the richness of the feed itself' were set by the ore (Scotch) hearth; on the contrary, the richer the feed, the better the results given by the hearth. The natural field of operation of the hearth, as determined by the ores available, was seen to lie in the Central United States, with their lead concentrates containing negligible quantities of precious metals and. with few ores of such metals available for use as fluxes. It was noted) however, that even in its chosen field, the Scotch hearth, or "ore" hearths developed from them, was not always used; the usual smelting practice was followed, at times, of sintering followed by blast-furnace smelting for even rich ores.

Jan 1, 1949

By Ren G. Dong, Kristine M. Krajnak, Dan Welcome

Continual occupational exposure to vibrating hand tools can damage the neural, vascular and other soft tissues of the fingers. Rat tail models have been developed to investigate the biological responses of the tissues to vibration.1-2 However, the biodynamic response of the tail relative to that of the human fingers has not been characterized. The objective of this pilot study was to compare the transmissibilities of rat tails measured via a scanning laser vibrometer to those of human fingers gripping a handle. Methods In Part I of this experiment, four male Sprague Dawley rats (6 weeks old) were exposed to discrete 5g-rms sinusoids of 32, 63, 125, 160, 250, and 500 Hz. The rats were restrained in Broome-style restrainers with their tails constrained without compression to an exposure platform via elastic straps as shown in Figure 1. The platform was attached to a vertically vibrating shaker. The vibration was measured for the array of points shown in Figure 1 using a scanning laser vibrometer (Polytec) and the transmissibility calculated for each point on the tail relative to the reference points on the platform. In Part II, three male human subjects were exposed at the frequencies specified in Part I - with the addition of 1000 Hz - at a magnitude at the ANSI <0.5-hr limit up to 63 Hz, after which the acceleration was held constant at 5g-rms. The subjects gripped an instrumented handle at 20 N as shown in Figure 2. The transmissibility was calculated relative to the reference points on the handle. [ ]

Jan 6, 2006

By T. L. Joseph

The purpose of this article is to describe briefly the operation of a 6-ton blast furnace on a charge of bauxite, limestone, iron ore, and cast-iron turnings and to point out the bearing which smelting such a charge has upon the production of alumina cement. One object of the experiment, conducted by the Bureau of Mines in cooperation with the Aluminum Co. of America, was to determine whether tae so-called Pedersen process3 can be applied to the blast furnace. This process consists of smelting a charge of bauxite, iron ore, and. limestone, and results in to products. One is a slag containing about 50 per cent of A1203 and is intended for use in manufacturing aluminum, and the other is iron low in sulphur. Complete details of the test are published in other reports4. Blast-furnace slag is now recognized as a satisfactory and economical raw material for making Portland cement, Wm. A. Forbes5 has recently reported that in 1926 an important steel interest used well over 1 million tons of slag in producing about 24 million long, tons of cement. This is equivalent to about ½ ton of slag for each ton of cement. Alumina cement can be made direct in the blast furnace. Its physical character would have to be changed by grinding, but no change in its chemical composition would be necessary.

Jan 1, 1928

By D. E. FOCG, A. E. Wells

When the United States entered the World War governmental agencies found little definite knowledge available as to the exact capacity of each sulphuric acid plant in the United States to manufacture acid under the stress of a great emergency. It is true that on account of the demand for acid for the manufacture of munitions for the Allies, prior to the entrance of this country into the war, most of the acid plants near industrial centers in the Eastern and Northern States were running at or nearly their maximum capacity, but, . for various reasons, many plants in these States and plants in other districts were not. For a number of years statistics as to the production of acid by the plants of the country were compiled by the United States Geological Survey, but obviously such figures did not give information as to the maximum capacities that might be available for meeting the he.a vy war ·requirements, or as to the steps that would have to be taken to bt-ing these capacities into use. During the summer and early fall of 1917 various attempts were made to obtain the desired information, but no satisfactory or complete data were obtained. Late in 1917, under the authority granted to the Bureau of Mines by the explosives act, the Director of the Bureau of Mines directed A. E. Wells, metallurgist of the bureau, to uiake a complete survey of the situation. Mr. Wells personally conferred with officials of the acid companies and visited most of the acid plants in the North that are east of the Mississippi River. The information obtained through this personal survey, together with that obtained through the ready cooperation of the subcommittee on ncids, and the subcommittee on fertilizers of the Committee on Chemicals of the Council of National Defense, enabled the preparation of a report containing the desired data concerning the sulphuric acid industry. This report was made immediately available to the War Industries Board and to those offices in the War and Navy Depart- ments that were most directly concerned in planning the explosives program and in obtaining the necessary supplies to produce the explosives. Beginning with this survey and report, the sulphuric acid section of the war minerals investigations of the Bureau of Mines took an active part in all matters pertaining to the sulphuric acid industry during the remainder of the war. Mr. Wells, the chief of the section, was appointed an associate chief of the sulphur, pyrite, and sulphuric acid sections of the War Industries Board. .Also, by this direct contact with the War Industries Board, the data obtained by Messrs. R. R. Hornor, H. A. Buehler, a.nd 0. Lindstrom, who were in charge, for the bureau, of the investigations concerning the supplies of pyrite and sulphur, were constantly made available to all interested Government agencies. D. E. Fogg, of New York City, was appointed chemical engineer to the sulphuric acid section to make special investigations relating to the acid industry, especially the possible utilization, in an emergency, of those sources of raw material.not then being used. Mr. E. E. Corbett, of Brooklyn, N. Y., was appointed chemical engineer to make investigations concerned primarily ,vith the conservation of acid. Direct and intimate contact with the industry was had through the close cooperation with the committee on acids of the Chemical Alliance, this committee during the greater part of 1918 occupying rooms with the acid section of the bureau. With the ending of the war and the close o:f the active work of the acid section of the bureau, the suggestion was made by many interested parties that a bulletin be prepared giving some qf the fun. damental and most important facts regarding the sulphuric acid industry, including a discussion of the technical :features of the manufacture of acid. During the war the bureau received -a vast number of inquiries in regard to various phases of the industry, a.nd this fact also made such a bulletin seem desirable. Therefore, the present bulletin was prepared to cover the main facts in regard to the industry in this country, including a discussion of the supplies of sulphur-bearing raw materials, the situation of the acid plants, the principal points in regard to manufacturing processes, and the uses of the acid. No attempt has been ma.de to discuss at length the manufacturing processes, as details differ more or less at the different plants and in general are carefully guarded by the acid ·companies. A great deal of the data given in this bulletin may be found in various pub]ications, but this is the first publication in which such data have been assembled and made readily available. Most of the data were obtained directly from observation and from cooperating acid companies or from individuals who had been or are now engaged in acid manufacturing and were liberal and generous in making their information available for publication. Care has been exercised to publish no data that were obtained as confidential by the bureau's representatives. The average acid manufacturer may be already more or less acquainted with most of the information presented in this bulletin, yet it is believed that the bulletin will be of value to those who wish to obtain a. general review of the present condition, both the economic and technical, of the sulphuric acid industry in the United States.

Jan 1, 1920

By GEORGE S. POPE

This bulletin is the third of a series a showing the results of ment purchases of coal according to specifications as to its quality and giving typical forms of proposals for supplying coal and general information relating to government coal purchases . Numerous calls for authentic information concerning the purchase of coal according to its heat value attest a growing interest in the subject. Many of the commodities of life have long been purchased according to specifications requiring chemical or physical tests , or both, to determine whether the material delivered meets the requirements , the price to be paid depending on the results of the tests . Until recent years coal consumers purchased coal merely on the statement of the dealer as to its quality , relying on his integrity and on the reputation of the mine or district from which the coal was obtained. It is surprising that the important question whether value was being received for the money expended was not sooner seriously considered . The purchase of coal by specification is an important step toward the conservation of our national mineral resources , for it results in an increased use of the lower grades of coal. The poorer coals find a market by competing with the better grades , not as to the price per ton but as to the cost of an equal number of heat units. This paper gives in detail the results of government purchases of coal for the fiscal year 1908–9 and the list of contracts with abstracts of specifications for the fiscal year 1909–10 , and summarizes the information on this subject obtained by the Survey. It is hoped that this information will promote a better understanding of the specification method of purchasing coal and furnish data valuable alike to coal dealers and coal consumers , so that equitable contracts can be more readily made.

Jan 1, 1910

By Dorsey A. Lyon, Robert M. Keeney

This bulletin is one of a series dealing with the application of the electric furnace to the smelting of ores and the manufacture of alloys, and is published by the Bureau of Mines in the endeavor to increase efficiency in metallurgical processes. The bulletin presents, first, a critical discussion of the possibility of smelting copper ores in the electric furnace; second, the results of the experimental work of other investigators on the electric smelting of copper; third, the results of experiments by the authors on the electric smelting of native copper concentrates and sulphide copper ores; and, fourth, a comparison of the electric furnace with the blast furnace and reverberatory furnace for copper smelting. Before considering the electric smelting of copper ores the reader should understand that the electric furnace was not developed as a competitor of the combustion furnace, but for the purpose of doing high-temperature work that can not be done in the combustion furnace, and for the treatment of ores from deposits that are in regions where fuel is scarce and costly but hydroelectric power is comparatively cheap, as in Chile, and in certain parts of Canada, the United States, and Mexico. Furthermore, it is not the object of this report to try to prove that the electric furnace should replace the reverberatory or the blast furnace, as used at present in smelting copper ores, but to show that the electric furnace may be used with advantage in localities where conditions are not favorable to the use of the reverberatory or the blast furnace. For example, otherwise valuable ore deposits may be situated in a district so remote from, or inaccessible by, railway that the cost of get- ting coke for smelting, or of transporting the ore to a smelter, is pro- hibitive. If there is sufficient water power at hand, from which electric power can be developed at a reasonable cost, and this electric power is used for smelting the ore in an electric furnace, with subse- quent bessemerizing, if necessary, the concentrated product may be

Jan 1, 1915

By J. Roger Loebenstein

This report presents a U.S. Bureau of Mines study of the flow of arsenic-containing materials in the United States, based on the best data available in 1991, includes a consideration of arsenic as a byproduct of the processing of nonferrous metals, the fate of arsenic in manufacturing wastes, the quantity of arsenic used in products, tile fate of arsenic in dissipative uses, and the useful life of discarded products. Where possible, estimates are given of the amounts of arsenic lost from the materials flow. Arsenic byproduct of mining nonferrous metals. Historically, most U.S. production has been from the states of Montana, Washington, and Utah. The smelters in these states are believed to be the areas of the country where arsenic is most concentrated in the soil, tailings ponds, and waste dumps. Since the closure of the last domestic producer of arsenic in 1985, all arsenic has been derived from imported sources. Historically, arsenic was important in agricultural applications as an insecticide, herbicide, and cotton desiccant. As the environmental movement gained momentum and the toxicity of arsenic became better understood, most of the agricultural uses for arsenic were banned. Beginning about 1975, the use of arsenic as a wood preservative began to grow. After 1980, wood preservative uses became more important than agricultural applications. By 1990, 70% of the arsenic consumed in the United States was used by the wood preservative industry and 20% by the agricultural industry. The major source of domestic arsenic emissions in 1989 was from the U.S. copper processing indus¬try. About 7,800 mt/yr of arsenic was discarded in leach dumps, tailings, and slag. Another 800 mt/yr was liberated to the atmosphere and 1/100 mt/yr was exported in copper concentrates. On the consumption side, 9,200 mt/yr was lost, mostly from dissipative agricultural uses and the disposal of obsolete arsenical products.

Jan 1, 1994

By Kung-Lee Wang

This report describes the linkage of all mining sectors with all other manufacturing, services, and final demand sectors of the U.S. economy. Besides being a basic data source, it provides a framework for aggregate economic impact analysis with respect to the mining industries. The framework is an open-static input-output model specifying 48 mining industries as classified in the Standard Industrial Classification Manual for all mining activities and 76 nonmining industries which collectively exhaust, all economic activities. The 124-sector model used in this report is an expansion of the preliminary 82-industry aggregation estimates made by the Department of Commerce. In the expanded model, 48 ruining industries are substituted for the original 6. The methodology used to ascertain the industry-by-industry procurement cost estimates and product ion flows necessary to the construction and expansion of the basic 82-sector model included personal interviews, case studies of specific mining activity analysis, and published and unpublished data from the Bureau of Mines and the Census of Mineral Industries, The end products of this study are two tables arranged to show the direct purchases necessary for each industry to support the level of economic activity and the total purchases generated in each industry throughout the economy by each $1 of aggregate economic demand in 1958. The tables may he used for economic impact studies and market analysis by firms engaged in or closely associated with the mining industries. Some illustrations of their usages are presented.

Jan 1, 1967

By R. H. Fernald

In investigating general problems that relate to the fuel resources of this country, and in testing fuels belonging to or for the use of the Government, the Bureau of Mines has given considerable attention to the efficiency and economic value of producer-gas power plants. Government inquiries during the past eight years not only have shown a very low fuel consumption per horsepower-hour for these plants but have demonstrated conclusively the possibility of utilizing commer- cially low grades of bituminous coal, lignite, and peat in plants prop- erly designed for the use of these fuels. The anthracite plant has been recognized as a commercial possibility for several years, although the cost of the fuel used has in general restricted these plants to com- paratively small units. The commercial development of the producer-gas power plant in the United States has been largely within the past six or eight years. In 1909 the United States Geological Survey published in a bulletin entitled "Recent Development of the Producer-Gas Power Plant in the United States" a list of producer-gas power-plant installations. The data presented in that bulletin showed a strong development in this field and led to much conjecture as to the future of this type of power. Owing to the extensive introduction of the steam turbine, however, many persons predicted the almost immediate doom of the producer-gas plant. In addition to the inroads made by this formida- ble rival, the interest of the gas-engine enthusiasts became centered to such an extent in the oil engine that the gas producer was relegated to second place by many and absolutely abandoned by some. During the past three years the belief of many who were formerly firm be- lievers in the gas producer has been that this type of power has reached its height of development in this country and that from a commercial standpoint it can no longer be regarded as a complete success. This feeling of commercial decadence has become so general

Jan 1, 1913