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By L. F. Heising

The Bureau of Mines evaluated 191 composites from the central Mesabi Range, Minn., chiefly by reductive roasting and magnetic separation. After reductive roasting and magnetic separation at minus 325 mesh, 28 composites produced concentrates that contained an average of 66.0 percent iron with less than 10 percent silica. Recovery of contained iron was over 90 percent. Natural magnetic material in excess of 5 percent was present in 142 composites. Trial flotation tests were used to evaluate three samples unresponsive to reductive roasting and magnetic separation procedures, and satisfactory concentrates having low silica contents (averaging 6.6 percent) were achieved.

Jan 1, 1965

By Mary S. Esfandiary

This is a revision of a directory of coal research organizations throughout the world that was first published in 1961 as Bureau of Mines Information Circular 8008. Because of the wide acceptance of the first edition, a revision which would supply up-to-date information on coal research and which would facilitate communication among organizations of similar interest seemed important. This compilation includes the names and activities of organizations of various types-government, university, private, and industry. The areas of investigation that each organization is engaged in are indicated in broad terms: Analysis and constitution, mining and geology, preparation, briquetting, combustion, high-and low-temperature carbonization, gasification, conversion to solid and liquid fuels, and health and safety. Publications issued by and describing the work of each organization are cited; almost all of the organizations also publish results of their investigations in the technical press. Selected technical and trade publications that publish information on the science and technology of coal and are not published directly by any of the organizations listed are cited in the pages following the list of organizations in each country. Information that would improve coverage and accuracy of the next revision of the publication will be welcomed by the Bureau of Mines.

Jan 1, 1966

By D. Harrington

For several years, or from about 1932 to 1935, inclusive, the coal industry of the United States had an excellent record as to coal-mine explosions. In 1937 and in 1938 to date there has been a definite increase in the number of explosions attended by considerable loss of life and property damage. In most of these explosions one important underlying and contributing cause has been lack of sufficient (or at least efficient) ventilation to properly dilute and remove explosive gas from the mine. This increase in explosions indicates that. the lesson taught through bitter experience, many times in the not far-distant past, of the need for good ventilation is frequently being overlooked, partly because the relatively good experience of the industry in the past several years has made many mining people forgetful. Moreover mining practices are rapidly changing, and in some instances the changes are being made with little if any regard for safety. It appears, therefore, that a review of some ventilation principles and practices should be of value in preventing further disasters; this paper has been prepared with that object in mind. In coal mining the need for thorough ventilation of all underground working places is recognized by both mining practice and law; such ventilation is generally obtained by the use of fans that circulate a quantity of air much in excess of the quantity of coal produced, by weight as well as by volume. For example, in a relatively small mine producing 1,000 tons of coal per day and circulating 100,000 cubic feet of air, which is by no means abnormal, 2,000,000 pounds of coal and approximately 10,900,000 pounds of air would be moved out of the mine every 24 hours. Because of the need for adequate dilution and removal of methane issuing or likely to issue from mine strata and for removal of the carbon dioxide formed by coal and timber oxidation up-to-date coal mines usually provide an air volume which if adequately coursed not only removes these gases but also the gaseous products of the detonation of explosives (which may include carbon monoxide, hydrogen sulphide, nitrogen oxides, carbon dioxide, and nitrogen) and the carbon

Jan 1, 1938

By Richard F. Hewlett

An attempt has been made to fit assay data from an underground copper deposit to a three-dimensional polynomial surface as a means of expressing assay points in terms of their mine coordinates by a mathematical equation. The resulting equation was evaluated to predict the grade trend of the deposit. Although the fit obtained by this initial experiment is not considered accurate enough to provide good predictions about the deposit, the methodology is presented in this preliminary report to show the potential usefulness of the technique in mineral deposit evaluation. The technique also should be useful in determining the grade of blocks of ore for production scheduling and blending problems in open pit operations. Further experimentation is needed to increase the reliability of the computer program, to increase the precision of the method, and to make the solution more flexible for use on other mineral deposits.

Jan 1, 1964

By John J. McClelland

The U.S. Bureau of Mines formed a team in 1991 to begin developing a long-range research plan for computer-assisted mining that would benefit the metal-nonmetal mining industry. This report details the team's accomplishments, specifically, the development of a model that identifies metal-nonmetal mining research needs that could be addressed by the application of automation technology. The report also provides a summary of automation needs and applications based on visits with mining company representatives. The status and future direction of this work is also presented.

Jan 1, 1994

By T. G. Mayhew, A. A. Bergeron, R. J. Mahany

This report describes an operational communications system which provides remote intra-terrestrial wireless transmission of environmental information. Design and modification specifications of requisite equipment are included along with a detailed description of system operation

Jan 9, 1976

By C. P. Bowie

[Frequent accidents in the transportation and. handling off petroleum and its more volatile products, serve as a reminder that this is indeed a hazardous undertaking and should always be conducted with due caution. On October 4, 1920, vapors in the held of the British tanks steamer G. R, Crowe became ignited and, caused an explosion which, it is reported, killed 5 men, injured. 40 others and endangered the lives of some 300 more. On November 10, 1920 the Morgan, Line freighter El Mundo was almost totally sot destroyed in New York harbor by fire caused by an explosion of gases in a fuel-oil tank. These two disastrous explosions emu emphasize the ever- present danger attending the use of petroleum products. This is also shown by the frequent occurrence of minor fires and explosions, caused by careless handling of baseline, which result in loss of life or serious injury to railroad employees, to oil-tank drivers, and to individuals in various walls of life. Statistics indicate that the lighter cuts of petroleum products, because of fire hazards, are dangerous, and are so considered by the railroad and other transportation companies. According o the Bureau of Explosives (Bar-eau of Explosives Report No. 13 p. 7) during 1919 transportation of gasoline in the United States resulted in 172 accidents, causing 2 deaths and 31 injuries, and a property loss to the extent of $687,966. Among the causes of ignition, an open light in the vicinity of the container stands out most prominently.]

Jan 1, 1920

By L. F. Christianson

The presence of salt in crude petroleum has been known for many years, but recently the percentage of chloride salts of calcium, magnesium, and sodium produced with some crude oils has increased to such an extent that the removal of the salty compounds is imperative for some refiners and their presence causes considerable apprehension for others. The exact reason for this increase of salts is not known definitely, but in all probability a combination of factors contributes to the condition. The most important are acidizing of wells, development of new fields producing crude oils of greater salt content, and the depletion of old fields with an attending increase in the production of emulsified brine. Due to handling

Jan 1, 1938

By L. F. Christianson

The presence of salt in crude petroleum has been known for many years, but recently the percentage of chloride salts of calcium, magnesium, and sodium produced with some crude oils has increased to such an extent that the removal of the salty compounds is imperative for some refiners and their presence causes considerable apprehension for others. The exact reason for this increase of salts is not known definitely, but in all probability a combination of factors contributes to the condition. The most important are acidizing of wells, development of new fields producing crude oils of greater salt content, and the depletion of old fields with an attending increase in the production of emulsified brine. Due to handling

Jan 1, 1938

By Robert E. Hershey

1. Estimates of reserves were made for three coal beds in Hamilton County the - Lantana, Sewanee, and Richland. Nine coal beds have been mined at one time or another in the county, but not enough information was available to estimate reserves in any beds other than the three given. 2. Known measured and indicated reserves for all beds, based on a minimum thickness of 14 inches and on 1,800 short tons per acre-foot of coal in place, are estimated to be 53 million tons as of January 1, 1954. Of this total 35 million tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics were insufficient for making an estimate conforming with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove re-serves in these areas, such reserves should be added to the total estimated reserves determined by this investigation.

Jan 1, 1956

By R. W. Stahl

A survey of firefighting facilities and practices in coal mines conducted by the Bureau of Mines3/ showed such variations in equipment and apparent attitude toward fire protection that a comparison with other industry seemed advisable. Although other industry is confined generally to surface operations and the hazards probably are not as great, the same general methods of extinguishment are employed, so that the cost and protection at least should be comparable. An investigation of industry other than mines revealed a generally greater emphasis placed on fire-combating equipment, fire-brigade training, fire-fighting facility inspection, and fire-hazard elimination, as well as a greater average expenditure for fire protection.

Jan 1, 1959

By Forrest T. Moyer

To keep the mineral and allied industries informed of trends in the causes of accidents and to point out the need for corrective measures, the Bureau of Mines collects, analyzes, and periodically published health and safety statistics. This report includes data for 1964 on injury experience, with related employment statistics, at coal mines in the United States. These data are presented in tabular form under the following headings: General Injury Experience Tables 1 to 6: Current data on number of injuries, degree of injury, frequency and severity rates, average severity, and related employment and production data by work location.

Jan 1, 1967

By W. M. Dressel

The Federal Bureau of Mines has obtained data by differential thermal analysis of the various minerals that represent the nation's resources in manganese. These data are supported by X-ray diffraction analysis, chemical analysis, mineralography, and optical mineralogy, and provide fundamental information on the response of each mineral to thermal treatment in oxidizing, reducing, and neutral atmospheres. The information can be applied advantage¬ously in the identification of manganese minerals. Its greatest potential value, however, lies in the application of the quantitative data on the reaction temperatures, rates, and products to the more efficient extraction of manganese from U.S. ores. Thermal analysis curves are presented for certain manganese minerals, namely hausmannite, bixbyite, braunite, pyrolusite, lithiophorite, cryptomelane, hollandite, manganite, rhodochrosite, and rhodonite. The original minerals and the products of their thermal decomposition were identified by X-ray diffraction analysis, supplemented by chemical analysis and mineralogical identification.

Jan 1, 1961

By R. B. Stroud

This report, part 3 of a series, describes and gives results of field. investigations by the Bureau of Mines on manganese resources of the Batesville district, Arkansas, from July 1956 through June 1961. The purpose of the Bureau's work was to evaluate the manganese potential of the district in fur- therance of the Government's program with respect to domestic resources of critical and strategic minerals. The work comprised areal reconnaissance, mapping, churn and core drilling, and sampling. In more recent years, the investigations were confined to manganiferous limestone, which constitutes a significant potential resource of manganiferous material. The resources of manganiferous material in the district are inferred to be on the order of 198 million long dry tons averaging between 4 and 5 percent manganese.

Jan 1, 1964

By A. C. Smith

The U.S. Bureau of Mines conducted a study to evaluate the effect of underground mining conditions on the activation of automatic sprinkler heads. Sprinklers were exposed to liquid fuel fires in a rectangular tunnel at airflows of 0, 45, 90, 150, and 250 m/min to determine the effect of ventilation and fire size on the time to activation. As the airflows were increased, the time to activate the sprinklers for a given fire size increased. Also, as the fire size increased, the activation time decreased. Temperature profiles of the tunnel showed that the maximum temperature near the roof was shifted downstream as the airflow increased. Experiments to determine the effect of rated activation temperature and response time index (RTI) value on activation time showed that the time to activate increased with increasing activation temperature, and decreased with decreasing RTI value. Exposure to the mine environment showed little effect on the activation times in large-scale experiments, and no significant effect in laboratory experiments. The results showed that airflow can have a significant effect on the activation times of automatic sprinklers. This needs to be considered in the design of effective sprinkler suppression systems for ventilated areas.

Jan 1, 2010

A revolutionary development in blasting materials has occurred in recent years. Ammonium nitrate, sensitized by the addition of a small percentage of No. (class) 2 diesel fuel or other suitable petroleum product, has been adopted as a low-cost, efficient blasting agent2 in a wide variety of mining, quarrying, and heavy construction operations. Moreover, the ready availability of the component supplies throughout the Nation, together with the ease of formulating them into effective blasting agents, has made it possible for the blaster himself to prepare the mixes at the site of use. Recently, most established explosives manufacturers have begun supplying premixed AN-FO (ammonium nitrate-fuel oil) or a comparable product to various mining operations. However, many individuals and small business establishments are marketing premixed products prepared in facilities that are often poorly constructed and poorly located. Although these blasting agents have partly or wholly displaced explosives such as dynamites in many applications, there are some blasting operations in which the fuel-sensitized ammonium nitrate agents do not appear to be well adapted. As long as the hazards they present are clearly understood and respected, ammonium nitrate-based blasting agents have important safety characteristics when prepared under competent factory control or field-mixed under equivalent close control. This publication attempts to summarize the knowledge of those hazards and to incorporate practical ways to cope with them.

Jan 1, 1963

By B. P. Martinez

In response to a request from the President, the Department of the Interior joined with other agencies in a comprehensive study of the land and water resources of the New England-New York region. As part of this study, chemical engineers of the Bureau of Mines have visited 1,025 mineral-industries plants to inventory the waterborne wastes of mineral origin, discharged by the mineral industries of the New England-New York region. Four-hundred and sixty-two of these plants disposed their wastes to a public sewer of some type, but waste control remains a problem for moat of them. The 1,025 plants are discussed in main industry groups according to their production: Chemical and allied products. Stone, clay, and glass products. Iron and steel and their products (except machinery). Nonferrous metals and their products. Electrical machinery. Machinery (except electrical). Transportation equipment. Miscellaneous mineral industries.

Jan 1, 1956

By G. L. Gates

The Bureau of Mines studied the scales formed in producing wells in the Wilmington field, California. The scales were primarily barium sulfate and resulted from the mixing of injected sea water and formation waters; there was excess sulfate in the injection water and the formation waters contained appreciable barium. After breakthrough, the produced brines were supersaturated with barium sulfate. Laboratory tests indicated that barium sulfate precipitated quickly When the supersaturated brines were agitated with crystals of barium sulfate and fairly rapidly when more sulfate solution was added. Precipitation occurred slowly on standing or under nonturbulent conditions. Both the apparent and equilibrium solubilities of barium sulfate in these brines were determined and compared with equilibrium solubilities in distilled water and sodium chloride solutions.

Jan 1, 1965

By Raja V. Rarnani, Robert L. Frantz

"Scientific, engineering, and biomedical research teams synergystically developed major topical research areas in the Respirable Dust Center. Descriptions of their interactions and resulting accomplishments demonstrate how cooperative research within and among these study groups benefits the overall respirable dust research and practical application needs of the mineral industries.The development of a state-of-the-art small animal inhalation exposure facility suitable for studies of fresh and aged coal mine dust, a major goal of this research group, will contribute toward the GTCRD goal of advancing the understanding of causative mechanisms for the occupation-related lung impairments and the airway diseases of mine and mill workers. Such understanding includes improved definition of the role of various aspects of the lung environment (e.g., surfactant and the mucociliary system) in the disposition and toxicity of respirable dust, comprehensive characterization of the role of the pulmonary alveolar macrophage (PAM) and its secretory products on the development of dust-related lung disorders, and an expanded search for methods to reduce the toxicity of respirable dust both before and after it enters the lung. The National Academy of Sciences has recommended, in Measurement and Control of Respirable Dust in Mines, that respirable dust research should include study of the behavioral and constitutional factors affecting individual susceptibility to workers' pneumoconiosis occupational disease and the development of methods for detecting the potential onset of pneumoconiosis earlier and more conclusively than can be done using X-ray methods. These recommendations have guided the research group in its goals of establishing and disseminating a scientific protocol for standardizing the inhalation testing for all research objectives within the Generic Center which involve small animal exposures and implementing the infrastructure necessary to make lung tissues obtained during inhalation studies available to all researchers within the Generic Center."

Jan 1, 1995

By E. R. Palowitch

This report stems from a study by the Bureau of Mines of the possibility of reducing coal filter-cake moisture by applying radiant heat directly to the filter cake while under vacuum during the drying phase of the filter cycle. One disk of a 4-foot-diameter vacuum filter was equipped with gas-fired radiant-heat generators and the effect of radiant heating on the moisture content of a variety of filter cakes was studied. The results of this investigation show that this process can best be described as a filter aid capable of increasing the effectiveness of conventional filtration approximately 6 percentage points of moisture. The operating cost of removing water by this method is somewhat lower than the average operating cost of thermal drying and is considerably cheaper when the total cost is considered. Removal of water from coal that has been wet-cleaned is an important part of the overall coal preparation process. Water is a contaminant, and it is foolish to wash coal to reduce its ash content and add inert water in the process. In some instances the removal of water is actually more important than the removal of ash-forming minerals; its weight adds to the cost of transportation, and its evaporation during burning or carbonizing absorbs useful heat. Fine coal that contains more than about 10 percent moisture is notoriously difficult to handle. A problem thus exists for which there are sound practical and economic reasons to seek a solution.

Jan 1, 1961