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By Lindsay D. Norman

Eleven major pyrometallurgical processes and operations suggested for recovering manganese from domestic resources are described. These include seven pyrometallurgical processes that usually yield a ferroalloy or a product from which ferromanganese can be produced in one operation. The remaining four involve pyrometallurgical operations whose products require either an additional two-stage process to produce ferromanganese or chemical processing to recover a high-quality manganese oxide product.

Jan 1, 1962

The principal activities of the Bureau of Mines Explosives Research Center from July 1, 1962, to June 30, 1963, are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1963; in general, the research reported in these publications antedates the report period.

Jan 1, 1965

By W. G. Sandell, L. C. Bauerle, K. C. Dean

"INTRODUCTION As a part of the wartime activities of the Bureau of Mines, metallurgical services were extended to other Government agncies engaged in purchasing and stock-piling some of the more critical and strategic materials. At the request of Dr. Alan M. Bateman, special representative of the Metals Reserve Company, metallurgical studies were made on three samples of oxide tin ore from, the States of Zacatecas and Guanajuato, Mexico. The samples were submitted for testing by A. Porraz of the Financiera Miners, S. A., institution Financiera, Edificio Guardiola, Despachos 500-507, Mexico, D. F.The samples as received were marked Nos. 1, 2, and 3 and described as follows:Sample 1. - Origin: Mining camp ""El Naranjo,"" municipality of Sombrerete, State of Zacatecas, Mexico. This sample was partly concentrated by washing and as received was all minus 10-mesh in size.Sample 2. - Origin: Deposits in Sierra. Fria and Juan Cherey, municipality, of Jerez,State of Zacatecas, Mexico. This sample represented run of-mine ore.Sample 3. - Origin: Mine ""La Frontere, "" Ranch of San Pedro del loya, State of Guanajuato, Mexico. This run-of-mine sample was low in tin content but came from a highly mineralized tin field."

Jun 1, 1947

By G. E. McElroy

This report discusses the construction and use of an all-pressure psychrometric chart in which the requirements of simplicity of appearance and absolute accuracy have been waived, to a certain extent, to provide for the rapid determination of psychrometric data and for the rapid solution of air-conditioning problems of major interest to the mining industry. Many mines in which air-conditioning problems are important are situated at elevations far above sea level and embrace great differences in elevation - in excess of 8,000 feet in certain mines - throughout their airflow circuits. Under these conditions, the effects of variations in the pressure of the atmosphere upon the physical properties of the mixture of air and water vapor of which it is composed are considerable and should be taken into account in the solution of problems. The simple types of psychrometric charts in common use, such as the Carrier, Bulkeley, Hill, and Goff (American Society of Heating and Ventilating Engineers Guide), are not generally suitable, in that they are drawn for a single barometric pressure - 29.92 inches mercury.

Dec 1, 1947

By P. A. Hendricks

This U.S. Bureau of Mines (USBM) report identifies and evaluates factors responsible for metal/nonmetal (M/NM) underground mining accidents involving mobile equipment. Information regarding the occurrence and severity of the accidents, the type of equipment involved, the primary and contributing causes, and preventive measures is included. The goal of this report is to provide information that will aid mine operators and safety managers in the recognition of hazards associated with operating mobile mining equipment in an underground mining environment.

Jan 1, 1994

The principal activities of the Bureau of Mines Explosives Research Center from July 1, 1962, to June 30, 1963, are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1963; in general, the research reported in these publications antedates the report period.

Jan 1, 1965

By George H. Schnakenberg

Automation of coal mining activities at the face offers improvements in worker safety, health, and productivity. Introduction of integrated computer-sensor systems to current mining machines will enable these machines to perform some of the most hazardous tasks through supervised teleoperation. The U.S. Bureau of Mines is pursuing the development of the enabling technology necessary to achieve this goal. The research program consists of both basic and applied research, each focused on the fundamental issues of computer and sensor technologies. Short-term research is directed to providing computer-assisted, remote supervisory operation of present underground equipment; the long-term goal is the development of progressively more intelligent mining systems. The research program includes a review of robotic machine and autonomous vehicle technologies and of current mining technology, which provides a base for developing innovative mining methods; research in navigation and guidance technology, emphasizing control of a continuous mining machine; research on coal-rock interface sensing technology for horizon control, and rib thickness control in highwall mining; the development of computer systems and hierarchical architectures for real-time control; and development of expert systems for machine system fault diagnostics and predictive maintenance. This report presents a brief background and the current status for each of these research areas.

Jan 1, 1989

The U.S. economy showed further strength during the third quarter of 1983, continuing the upward trend discussed in the last two issues of Minerals and Materials. The National Association of Purchasing Management composite index increased to a 10-year high of 67. 1 in July. (A value of 50 or greater indicates expanding industrial activity.) The index, a weighted composite of new orders, production, employment, vendor performance, and inventories, is derived from a survey of purchasing agents for about 250 industrial firms. Investment and Other National Economic Indicators The strong consumer surge of second quarter 1983 was reinforced during the third quarter by the performance of private investment. Because of this, many analysts became more optimistic about the strength of the recovery and its potential for being sustained. Capital investment growth, negative since 1980, was positive for every investment component in the third quarter of 1983. Preliminary estimates indicate a real increase of $1.4 billion (at an annual rate) in private investment expenditures on nonresidential structures, an increase of $4.3 billion (at an annual rate) for producers' durable equipment, and an increase of $4.8 billion (at an annual rate) in real inventory levels. The second quarter 1983 increase in expenditures on producers' durable equipment was the first indicator that investment recovery would occur during the rest of the year (table 1). Corporate profits in total manufacturing increased $6.5 billion from first quarter to second quarter 1983 (table 2).

Jan 1, 1983

By R. J. Marek

The number of persons fatally injured in the California petroleum industry in 1931 was 30, a decrease of 20 fatalities or 40 per cent from the number killed in 1930. As a result of the decrease in the number of fatalities for 1931, the fatality curve of the California petroleum industry reached its lowest point in nine years. Although reductions in personnel--which permitted the retention of a select and experienced class of workmen, decreased active field-development work, and curtailed production--undoubtedly have had a marked effect on reducing the number of fatalities in 1931, the decrease also has resulted from continued accident-prevention efforts. Statistics show that a direct relationship exists between development activity and the number of men accidentally killed in the drilling and producing division of the California petroleum industry. For example, when the average number of drilling wells in 1930 was 29 per cent less than in 1929, the number of men accidentally killed at drilling wells dropped 48 per cent; and when the average number of drilling wells in 1931 decreased 52 per cent from 1930, the number of fatalities at drilling wells decreased 58 per cent. The relationship between field-development work and fatality frequency is significant because each year at least 50 per cent of all the fatalities in the California petroleum industry occur in the drilling and producing division. This relationship should serve to guide the accident-prevention efforts of the industry, especially in the drilling and producing division, toward checking an increase in fatal accidents when development activity again takes an upward trend.

Jan 1, 1932

By John C. Holtz

"The Federal Bureau of Mines serves the mining industry by approving equipment that is designed to prevent explosion, fire, shock, or toxic hazards in mines when such equipment is used and maintained in a proper manner, through research, consultation, testing, and inspection, the Bureau studies machinery and component parts submitted by manufacturers and others. Before receiving the Bureau's approval as permissible for safe use in mines, equipment must pass exacting tests and must meet strict requirements established through research and experience and listed in the Bureau's various permissibility schedules. An important phase of the Bureau's research is the testing of diesel engines.Mobile diesel-powered equipment can be used safely in underground noncoal mines and tunnels when mechanical ventilation is provided to dilute and remove the exhaust gas and to replenish oxygen in the underground atmosphere. Safe ventilation is determined by suitable tests of each engine used in a diesel machine. This ventilation cannot be predicted safely, accurately, and economically from any general empirical relationship.In determining safe ventilation, the quantities of carbon dioxide, carbon monoxide, and oxides of nitrogen generated by a diesel engine must be ascertained. These quantities are related to the displacement of the engine, its speed of operation, the design of the combustion chamber, and the fuel:air ratio needed to produce useful power. At overrich fuel:air ratios, all diesel engines generate excessive quantities of toxic carbon monoxide and smoke. The results of engine tests are used to determine a maximum fuel-injection rate at or below which carbon monoxide can be controlled by a reasonable ventilation and smoke is essentially eliminated. Toxic oxides of nitrogen are related to fuel:air ratio and the design of the combustion chamber. Their concentration in the exhaust cannot be controlled by engine adjustments, and each engine appears to have individual characteristics concerning formation of these oxides. Production of oxides of nitrogen frequently is the most important factor in determining safe ventilation."

Oct 1, 1959

By Kenneth E. Hay

The Bureau of Mines collected coal and coal waste aggregate material from two different mine sites to determine their strength characteristics for use in concrete. The concrete would be placed underground as support walls for ground control in adverse conditions or unique mining applications. A standard mix design was established for a "wet" mix using a water-to-cement (w/c) ratio of 1.0 to facilitate pumping into place. Later, material was collected from four more mine sites and used to make 2-by 2-by 2-ft test blocks with the same w/c ratio. A pull-out cone device and borehole shear tester were used to determine the in situ material strength of the test blocks. These techniques will provide a simple and quick way of determining support wall strength in an underground environment. Test results from the pullout cone de-vice showed a good correlation of 0.98 to test cylinder compressive strengths of the same mix. Results of the borehole shear tester were inconclusive.

Jan 1, 1986

By G. M. Kintz

It is estimated that 10,000 lives were lost and $285,000,000 worth of property was destroyed by fire in 1937. Of the 103 fatalities in tie petroleum industry in 1938, 36 resulted from fires and explosions.3/ Everyone can help to prevent the tremendous losses, both in life and property, caused annually by fires and explosions, Forest fires occur every year, in which the tremendously intense heat wave ahead of the flame turns beautiful green trees into blazing torches like so much gasoline, vapor, and jumps over the tops of trees to start fires behind the firs fighters; prairie-grass fires occur, and a farmer in the path of the fire must plow a furrow around his home and outbuildings before the flame reaches them; and frequently automobiles are burned up in filling stations. Persons who have witnessed such sights know better than to throw a lighted match, cigarette, cigar, or hot coal from a pipe out of an automobile or to discard a fire or flame of any type in the forest, in the country, or in the city.

Jan 1, 1941

During development mining, ventilation capacity may decrease and the ventilation requirements may depart from initially planned values depending on the mining rate, increases in the methane emission rate, and changes in ventilation airway leakages. Insufficient ventilation air quantities and the occurrences of high methane liberation rates can overwhelm the existing quantity of ventilation air and result in elevated levels of methane gas during development mining. This condition can both limit the development of that section and increase the risk for an ignition that may lead to an explosion. Thus, the prediction of ventilation air requirements prior to mining can enhance worker safety by reducing the likelihood that explosive methane-air mixtures form. This study presents an approach for prediction of methane inflow rates using coalbed methane reservoir modeling. For this purpose, a two-phase coalbed reservoir model of a three-entry type roadway is developed. In the model, grids are dynamically controlled to simulate development of entries. Examples are given for methane inflow and ventilation air requirements as a function of mining rate, development section length, mining height, and the existence of degasification boreholes. This technology can be used to limit the methane concentrations occurring as a result of the influences of various coalbed and operational parameters.

Jan 1, 2008

By Shigeru Tsutsumi

The rapid development of transportation facilities in Japan focused the attention of this country on the possibility of converting the existing coal resources (of which there was an abundance) into liquid fuels, for which there was a constantly increasing demand. Previous work had indicated that this could be accomplished by utilizing one of two processes - the Bergius process, in which high temperatures and high pressures were employed to effect direct liquefaction of the coal, and the Fischer-Tropsch process, in which an indirect liquefaction of coal was accomplished by the production of liquid hydro-carbons from hydrogen-carbon monoxide mixtures. This report describes some investigations into the latter process, which was first developed by Fischer and his colleagues in the Coal Laboratory in Muhlheim, Germany, in 1923. By 1932, these investigators had achieved a 60-percent theoretical yield (152 ml. of liquid hydrocarbons per cubic meter of 2H2:ICO synthesis gas) by using a precipitated Co-Th02 catalyst.3/ At the same time (1932), Dr. Kita of Kyoto Imperial University and Messrs. Fujimura and Tsuneoka obtained 145 ml. of gasoline (C5+) per cubic meter of synthetic gas by using a Co-Cu-Th-U catalyst. 4/ This report is a description of the experimental results subsequently obtained at the Fuel Research Institute, Kawaguchi City, Saitama, up to 1935.

Jan 1, 1951

The analysis of in-mine grounding systems began with an extensive literature search which is still in progress. About a dozen articles have been found which deal directly with grounding problems on low voltage power systems or mine power systems. These systems have special grounding problems because normal load currents can be nearly as large as many types of fault currents. Information has been collected on the influence of cable spacing) conduit geometry, location of nearby conducting structures, etc., on the magnitude and path of fault current. Many other articles have been found which are less directly related to mine ground system analysis. The in-mine ground system analysis team has also inspected portions of two mine power systems to become familiar with the practices used in grounding. One electrical engineer and several other mine personnel have been interviewed concerning mine power system grounding practice. Already several aspects of the mine grounding system have been marked as requiring special attention.

Jan 1, 1975

By E. M. SEELEY, F. S. LOTT

Expansion in total capacity of the natural-gasoline industry.to produce light products continued in 1944 and 1945. The average rate of gain, however, was reduced to about 6 percent annually from over 9 percent in the preceding 4-year period. New facilities at cycle plants again accounted for most of the increase in productive capacity. Between January 1, 1944, and January 1, 1946, the number of cycle plants increased from 32 to 37 and their total capacity from 3,278 thousand gallons daily to 4,848 thousand (48 percent). Capacity of all other plants in the industry increased in the same period from 12,735 thousand gallons daily to 13,080 thousand, or only 3 percent. The capacity of the average plant increased to 28,600 gallons a day from 24,400 gallons on January 1, 1944, continuing the established trend. The average capacity of cycle plants increased to 131,000 gallons a day from 102,400 gallons, and the average capacity of all other natural-gasoline plants increased to 22,200 gallons a day from 20,400 gallons. Although the number of plants increased in only three States in the 2-year period (Texas, Okla- homa, and Arkansas), the total capacity of plants increased in eight States. A further decline of 29 reduced the total number of plants to 626 on January 1, 1946. Compared with 10 years earlier, gasoline plants were more numerous in only 4 States: Texas (48 more), New Mexico (7 more), Arkansas (2 more), and Louisiana (1 more). The largest declines, in order, were in Oklahoma, Illinois, Pennsylvania, West Virginia, and California. The number of plants with fractionating equipment for separating the liquefied gases from heavier fractions was 202 on January 1, 1946 and 182 2 years earlier. The principal changes in number and capacity of shut-down plants were an increase in Texas and a decrease in California. Shut-down natural-gaso- line plants are usually among the smallest units in their vicinity.

Apr 1, 1947

By W. W. Adams

"The results of the fourth annual safety contest, 'mown as the National Safety Competition, contacted by the United States Bureau of Mines are herein announced. A bronze trophy, ‘Sentinels of Safety’, the gift of the Explosives Engineer magazine, has been awarded to the leading mine in each of the five groups into which the mines and quarries that participated in the contest were arranged. These five groups were: anthracite mines, bituminous coal mines, metal mines, nonmetallic-mineral mines, and carries and open-pit mines. The leading plant in each group was the mine whose employee lost the smallest number of days from accidents in proportion to the total number of man hours worked. Where two or more mines operated without a lost-time accident, the winner was adjudged to be the plant which operated the largest number of man hours during the year.The contest was based upon reports of accidents and exposure sent by the competing companies to the Bureau of Mines. Records of the five leading companies in each group were made known to a Committee of Award, consisting of the following seven members: H. Poster Bain, Secretary of the American Institute of Mining and Metallurgical Engineers; James F. Callbreath, Secretary of the American Mining Congress; W. H. Cameron, Managing Director of the National Safety Council; H. L. Gandy, Secretary of the National Coal Association; A. T. Goldbeck, Director of the Engineering Bureau of the National Crushed Stone Association; William Green, President of the American Federation of Labor; and A. J. R. Curtis, Assistant to the General Manager of the Portland Cement Association. Members of the committee voted for the winning company in each group in accordance with the rules governing the contest.. A majority vote prevailed."

May 1, 1929

By R. S. Handy

This paper describing the milling practices at tae concentrators of the Bunker Hill and Sullivan Mining and Concentrating Co. is one of a series being prepared by the United States Bureau of Mines on milling methods and costs in the United States. The possibility of useful comparisons has prompted the description of all five of the mills operated by the Bunker Hill and Sullivan Company in northern Idaho. The general features of these mills are tabulated below: [ ]

Jan 1, 1930

By J. J. Demeter

As part of its work on converting coal to fluid fuels, the Federal Bureau of Mines has been studying the synthesis of liquid fuels from carbon monoxide and hydrogen by Fischer-Tropsch synthesis. A fluidized bed of nitrided, fused-iron catalyst has been operated successfully to produce high yields of oxygenated compounds. Trouble-free operation continued for over 800 hours, and the test was terminated voluntarily. About 85 percent of the fresh feed was converted when the unit was operated at a space velocity of 500 hr.-1, a 12:1 recycle-to-fresh-feed-gas ratio, a 300-p. s. i. g. pressure, and a temperature of 252° C. When operating at a fresh-feed-gas space velocity of 1,000 hr.-l and a 9:1 ratio of recycle to fresh gas, conversion of fresh feed was 68 percent, and the product yield was 235.9 grams per cubic meter of synthesis gas converted. The oxygenate and C5 and heavier hydrocarbon yield was 110.6 grams per cubic meter of gas converted, 83 percent of this was oxygenates. The atom ratio of N:Fe of the catalyst, initially 0.455, decreased to 0.288 by the end of the 800-hour experiment. Nevertheless, the yield of oxygenated compounds per cubic meter of H2 + CO converted at the end of the run was approximately the same as that obtained 500 hours earlier with identical operating conditions. X-ray analysis of the discharged catalyst indicated that only ?-iron carbonitride was present. Sieve analysis of the discharged catalyst indicated that only 2 percent of fines was produced during the reduction, nitriding, and synthesis.

Jan 1, 1959

By R. W. Geehan

The Bureau of Mines has been investigating deposits of critical and essential minerals in the United States since 1939. Bureau engineers made a preliminary examination of the Morefield mine early in 1943 and recommended investigation by trenching and diamond drilling, The Bureau of Mines conducted work from August to December of 1943, which indicated that the Morefield mine was a favorable location for an experimental mining program. The Bureau of Mines carried on such a program from September 1947 to March 1949. The property investigated is 30 miles southwest of Richmond in Amelia County, Va. (fig. 1). During World War II mica and beryl were shipped from the Morefield mine, but after the high prices and premiums paid during the war years were not available the mine was closed.

Jan 1, 1953