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By Launa Mallett, Charles Vaught, Michael Brnich, ROBERT PETERS

Interviews of 48 miners who escaped underground coal mine fires revealed that none of them had ever, before that incident, worn their self-contained self-rescuer (SCSR) either in training or in a real emergency. Consequently, they were ill-prepared to use this emergency breathing apparatus. One persistent problem stemmed from the fact that miners had no notion of breathing resistance, nor of the fact that it would get more difficult to breathe the longer they wore their device. As a result, many of those who were interviewed had simply removed their mouthpieces and breathed ambient air. This is obviously behavior that should be trained out of the workforce. Unfortunately, because of high costs and difficult logistics, miner training is unlikely to ever include donning and wearing an apparatus on a regular basis. In order to give workers a better idea of what to expect from their devices, therefore, the National Institute for Occupational Safety and Health researchers developed a tabletop (paper and pencil) simulation based upon actual predicaments evacuees had reported encountering. The simulation is designed to emphasize important points related to donning and wearing a self-contained self-rescuer in a mine fire escape, and, by doing so, to bring miners' expectations more in line with what their actual experiences would be. The simulation was field tested in six training classes at three different mining operations. In all, 99 individuals were involved in completing the exercise and rating its properties. In their ratings 88% of the respondents indicated they thought the scenario could definitely happen in real life, and over 80% agreed they had learned something new. From the field test data it was concluded that the simulation had authenticity and potential value as a teaching tool. The simulation was therefore used in a pre-test/post-test control group experiment to determine whether it led to improvements in miners' scores on a true-false test of their SCSR's functional capabilities and proper usage. Eighty-three miners were included in this part of the study. As expected, miners who had participated in the training exercise scored significantly higher on their post-test than miners who had not.

By John A. Breslin

This report summarizes the principal activities and significant results of the Bureau of Mines respirable dust research program since passage of the Federal Coal Mine Health and Safety Act of 1969 and the Federal Mine Safety and Health Amendments Act of 1977. This program has investigated new and improved techniques and equipment to reduce or prevent the formation of dust during the cutting cycle; to dilute, suppress, or collect airborne dust generated during mining, handling, and processing; and to improve the measurement of dust levels for evaluation of engineering controls and for enforcement of Federal dust standards. The report is intended for mining industry dust control specialists and other interested parties. It includes a brief summary of the program to date, a section on future research plans and goals, and a list of publications resulting from the Bureau's respirable dust program.

Jan 1, 1982

By Albert W. Deurbrouck

This report describes the preparation characteristics of the significant coalbeds in Russell County , Va . Almost 2 million tons of coal was mined in 1961 ; 75 percent of the coal was cleaned mechanically in preparation plants in the county . The coal of Russell County is ranked as medium- to high- volatile bituminous , contains small amounts of sulfur , and generally requires some cleaning to reduce the ash content to limits acceptable for metallurgical purposes .

Jan 1, 1963

By G. R. Hopkins

A recently completed survey , made by the Bureau of Mines to determine the trend of fuel consumption at refineries in the United States , showed the following outstanding points : A decrease in the use of oil for fuel in 1927 of over 5,000,000 barrels as compared with 1926 ; a decrease in the use of coal of over : 1,000,000 short tons ; small increases in the use of both natural gas and refinery gas ; an increase in the use of petroleum coke . The decrease in fuel - oil consumption was approximately 2,000,000 barrels each in the Atlantic Coast , Texas , and Louisiana- Arkansas districts , with an increase of 1,000,000 barrels in the Indiana - Illinois district , or a net decrease of 5,000,000 barrels . The decrease in fuel- oil consumption by refineries in the Texas and Louisiana- Arkansas areas was offset largely by increased consumption of natural gas and refinery gas , whereas the increased consumption in the Indiana- Illinois region was more than offset by the decrease in coal consumption . The use of coal for fuel declined from 6,052,000 short tons in 1926 to 5,031,000 short tons in 1927. Practically all of this decrease was recorded in the Appalachian and Indiana- Illinois districts , which at the same time showed the largest percentage increase in the use of oil for fuel . It is probable , therefore , that although coal prices also fell off , a considerable quantity of oil replaced coal in this area in 1927. In addition , the group of refineries , which are by location more or less definitely committed to the use of coal for fuel , undoubtedly succeeded in saving a material amount of coal through the use of more efficient fueling methods . A total of 130,815,000,000 cubic feet of natural gas was consumed for fuel at refineries in 1927. This represents an increase of 8 per cent over the 1926 total . Nearly all of this increase resulted from the opening of a line from the Monroe field to Baton Rouge , La . Had this line not been opened , there would have been a decrease in the use of natural gas , as a number of districts , particularly the Rocky Mountain , reported decreases in its use . The use of refinery or still gases for fuel did not change materially during 1927 , there being a total of 52,807,000,000 cubic feet burned as compared with 52,077,000,000 cubic feet in 1926. Refinery gases are largely a product of cracking and , it was probably more than a coincidence that a few districts in which cracking slowed down in 1927 also reported less refinery gas used as fuel .

Jun 1, 1924

By L. Crocker

The Bureau of Mines investigated processes for recovering a marketable lithium product from the montmorillonite-type clays of the McDermitt caldera. The clay deposit, located on the Nevada-Oregon border, is estimated to contain over 3 million short tons of lithium. Limestone-gypsum roasting and selective chlorination proved most successful for extracting lithium from the clays; 80-pct Li recovery was achieved using either technique. With both processes, lithium silicate in the clay was converted to a water-soluble compound-either lithium sulfate or lithium chloride. The lithium was then recovered as a carbonate by water leaching the calcine, concentrating the leach solution by evaporation, and precipitating the lithium with soda ash. The operating costs for the limestone-gypsum roast process were estimated at $2.02/lb Li2C03; selective chlorination operating costs were estimated at $3.85/1b Li2C03. The current selling price of Li2C03 is about $1.50/lb. A detailed flowsheet, material balance, and process evaluation are presented for the limestone-gypsum roast process. In addition, lithium reserves and resources are discussed and the McDermitt clays are described.

Jan 1, 1988

By H. C. Carpenter

Data are presented comparing results obtained with 17 different catalysts in hydrogenating crude shale oil to gasoline in single-pass operation. A method is described for predicting the maximum yield of gasoline obtainable at constant pressure for each catalyst from results of a limited number of experiments at different temperatures. Operating variables have considerable influence on yields and properties of products. With most of the catalysts, at operating temperatures below 890° F. liquid yield exceeded 100 volume-percent. Above this temperature the volume of liquid product decreased rapidly. Maximum gasoline production in most instances was achieved at a temperature higher than that at which the maximum volume of liquid product was produced.

Jan 1, 1959

By Jonnie M. Estes

A two-constant equation is presented for helium from 30° = T = 1,473° K. This equation is developed by modifying a generalized equation of state originally presented by Redlich and Kwong (20).3 The modification consists of setting B = 0.06372 Tc/PeT. This modified equation represents the compressibility factors of each of 80 isotherms tested in this temperature range to less than 1 percent average deviation.

Jan 1, 1967

By John A. Organiscak

Enclosed cabs are a primary means of reducing equipment operators? silica dust exposure at surface mines. The National Institute for Occupational Safety and Health experimentally investigated various factor effects on cab air filtration system performance. The factors investi­gated were intake filter efficiency, intake air leakage, intake filter loading (filter flow resistance), recirculation filter use, and wind effects on cab particulate penetration. Adding an intake pressurizer fan to the filtration system was also investigated. Results indicate that intake filter efficiency and recirculation filter use were the two most influential factors on cab penetration performance. Use of the recirculation filter reduced cab penetration by usually an order of magnitude over the intake air filter alone because of the multi­plicative filtration of the cab interior air. Intake air leakage and filter loading affected the cab penetration to a lesser extent, while wind had the least impact on cab penetration between the calm and 10-mph wind velocities tested. Adding an intake pressurizer fan notably increased intake airflow and cab pressure with only minor changes to cab penetration. A mathematical model was developed that describes cab penetration in terms of intake filter efficiency, intake air quantity, intake air leakage, recirculation filter efficiency, recirculation filter quantity, and wind penetration.

Jan 1, 2008

By John A. Organiscak

Enclosed cabs are a primary means of reducing equipment operators? silica dust exposure at surface mines. The National Institute for Occupational Safety and Health experimentally investigated various factor effects on cab air filtration system performance. The factors investi­gated were intake filter efficiency, intake air leakage, intake filter loading (filter flow resistance), recirculation filter use, and wind effects on cab particulate penetration. Adding an intake pressurizer fan to the filtration system was also investigated. Results indicate that intake filter efficiency and recirculation filter use were the two most influential factors on cab penetration performance. Use of the recirculation filter reduced cab penetration by usually an order of magnitude over the intake air filter alone because of the multi­plicative filtration of the cab interior air. Intake air leakage and filter loading affected the cab penetration to a lesser extent, while wind had the least impact on cab penetration between the calm and 10-mph wind velocities tested. Adding an intake pressurizer fan notably increased intake airflow and cab pressure with only minor changes to cab penetration. A mathematical model was developed that describes cab penetration in terms of intake filter efficiency, intake air quantity, intake air leakage, recirculation filter efficiency, recirculation filter quantity, and wind penetration.

Nov 1, 2008

By Michael E. Henderson

The U.S. Bureau of Mines (BOM) constructed the Hydraulic Transport Research Facility (HTRF) to investigate the hydraulic parameters relating to the transport of coarse coal. To achieve these goals in a timely and efficient manner, the Bureau contracted to Boeing Services International, Inc. (BSI) the responsibility of operating the HTRF and providing technical support. This data report is a summary of the testing and data results for the period from 16 September to 1 November 1983. The testing covered herein is for coarse 2-in by a (minus 50 mm) Pittsburgh Seam coal in a 12-in (3 00 mm) pipeline, at velocities ranging from 5 to 18 ft/s (1.5 to 5.5 m/s) and at concentrations ranging from 15 to 55 pct.

Jan 1, 1985

By J. M. Stuve

Thermodynamic properties were determined by the Bureau of Mines for the intermetallic compound, TiA13. Heat capacities were obtained from 5 to 303 K by adiabatic calorimetry. The derived value of S2 1s is 22.08±0.07 cal/deg¬mole. Enthalpies relative to 298 K were obtained from 298 to 1,413 K by copper-block drop calorimetry. No anomalous thermal behavior was noted in the temperature ranges investigated. Low- and high-temperature data were combined with a known enthalpy of formation at 298 K to give values of enthalpy of formation and Gibbs energy formation, 0 to 1,400 K.

Jan 1, 1974

By G. S. Price

This paper, which describes the milling practice at the Page concentrator of the Federal Mining and Smelting Co., is one of a series being prepared by the Bureau of Mines. The Page mine and mill are located on Silver Creek, 3 miles west of Kellogg, Idaho, and 1 mile south of United States Highway No. 10. Supplies and concentrates are hauled by truck over an automobile road which connects Highway No. 10 with the property. The concentrator has capacity to treat 300 tons of ore per day and utilizes all-flotation methods of treatment. Power is supplied from the main line of the Washington Water Power Co. which runs from Spokane, Wash., to Kellogg, Idaho. Water is obtained from the mine and also from a well which is situated 1 mile distant from the concentrator and about 600 feet in elevation below the concentrator.

Jan 1, 1932

By J. J. Bean

This paper, describing the milling practice at the oxide concentrator of the International Smelting Co., is one of a series on milling methods and costs being published by the United States Bureau of Mines. GENERAL DESCRIPTION The oxide concentrator is properly an integral part of the Tooele plant of the. International melting Co., located 5 miles from Tooele, Tooele County, Utah. It has a capacity of 300 tons of ore per day and uses an all-flotation process to treat custom siliceous oxidized lead ores obtained principally from the Tintic district in Utah. Ores found amenable to the process are purchased on a custom basis, the principal tonnages being obtained from the Tintic Standard and North Lily mines.

Jan 1, 1933

By Arcy R., D&apos George

The Bureau of Mines has developed, on a laboratory scale, a superior Eluex-type circuit for eluting and recovering uranium from ion exchange resins. The improved circuit differs from conventional Eluex practice in that a stage of uranium solvent extraction is coupled with each stage of resin elution rather than the elution and solvent extraction operations being conducted separately. The new system reduces the number of stages, retention time, and resin inventory in the elution circuit to one-fourth or one-fifth that in existing circuits. The system is applicable to both resin-in-pulp and moving-bed-type ion exchange uranium recovery circuits.

Jan 1, 1969

By S. P. Kinney

[The blast-furnace operator is often confronted with the problem of determining the size of the materials which are used in the furnace burden. The statement is heard that the coke is larger or smaller or that certain ore is finer than that previously used. A screen analysis of the materials used gives a measure of the different sizes of materials in an aggregate. When one is fine and the other is coarse, the difference is obvious; but when the materials are of similar sire, it is more difficult to estimate the degree of finances or coarseness. In considering raw materials it would be desirable to be able to judge the size of the radio ideal materials entering the furnace and the burden as a whole, by one representative value, such as the average size of particle. Previous work by Perrott and Kinney3 developed a method for measuring the average size of particle in a mass of finely ground materials, and an attempt will be made to apply this method to the materials included in the blast-furnace charge and to the entire burden.]

Jan 1, 1930

By J. B. Stephenson

The Bureau of Mines, under an interagency agreement with the Department of Energy (DOE), investigated the feasibility of hardfacing the critical surfaces of valves and similar devices by chemical vapor deposition. The purpose of this research was to increase the wear resistance of these components for use in the abrasive and erosive environment of coal gasification units. Tungsten and molybdenum coatings were produced on nickel-plated carbon steels and stain-less steels by hydrogen reduction of the metal hexafluoride at 325° to 600° C. Titanium nitride coatings were produced on low-carbon steels by the reaction of titanium tetrachloride, hydrogen, and nitrogen at 1,000° C. Titanium carbonitride coatings were produced on low-carbon steels by the reaction of nitrogen, hydrogen, and methane at 900° C. Tungsten, molybdenum and titanium nitride coatings were formed on 6-, 10-, and l2-inch (0.15-, 0.25-, and 0.30-meter) ball valve seats for evaluation in the low-Btu coal gasification pilot plant at the Morgantown Energy Research Center, Morgantown, W. Va.

Jan 1, 1979

By Forrest T. Moyer, J. I. DAVIS, JOSEPH H. SCHUSTER, E. K. ELSNER

The National Safety Competition conducted by the Bureau of Mines, United States Department of the Interior, is held each year for the purpose of promoting safety in the mineral industries of the United States. Since the program was inaugurated in 1925, twenty-three safety competitions have been held. This publication is a report of the results of the contests held in 1944, 1945, 1946, and 1947. The names of plants that have been awarded "Sentinels of Safety" trophies and Certificates of Achievement in Safety dur- ing these years, together with a summary of their achievements in injury prevention, are listed. Statistical data covering the injury experience of all plants entered in the annual contests also are included in this publi- cation. The injury statistics of these plants, arranged in the six groups of the competition, are the only data on injury severity at mineral operations available to the Bureau of Mines. Interest in the National Safety Competition has increased steadily. The number of participating plants has increased from 210 in 1925, the first year of the competition, to the record number of 494 in 1946. The widening scope of the competition means that a steadily increasing number of the mines and quarries in the United States are participating in a program that will supplement their other activities in promoting safety. Safety competitions have long been recognized as instrumental in stimulating and holding the interest of employees and officials in accident-prevention work. During the years covered by this report, conditions in the mineral industries of the United States were hardly conducive to setting records in accident prevention. During the war years, handicaps were especially severe- loss of skilled employees to the armed forces or to higher-wage war industries, greater production by a smaller force of workers, relatively high rates of labor turn-over, the longer workday in effect through 1944 and 1945, and difficulties in obtaining repairs and replacement for badly worn machinery. Even the immediate postwar period has brought no abatement of the tremendous pressure upon the mineral industries for greater production. Although there was a decrease of 18 in 1947 from the record enrollment in 1946, these oper- ations worked 160,525,025 man-hours, the greatest number of man-hours of exposure to mining hazards in any year of the contest except 1942. Despite the accelerated pace at which the mineral industry worked during the 4 years covered by this report, participants in the National Safety Competition have achieved creditable performances in the promotion of safety. In fact, the injury-severity rate in the enrolled plants in the 1947 contest was 7.315 days for each thousand man-hours worked, the lowest by far in the history of the National Safety Competition. The injury-frequency rate of 42.155 for each million man-hours of exposure to mine hazards in 1947 marks a favorable trend downward from the rate of 50.577 in 1946, which was the

Dec 1, 1949

By David E. Morse

Burundi, a small central African republic located between Tanzania and Zaire, remained essentially a nation of small family farms in 1978-79 with approximately 95% of the population engaged in subsistance agriculture. Coffee and tea continued as the nation's major export commodities. Mineral exports, small tonnages of cassiterite, wolframite and bastnasite, accounted for an estimated 3% of total exports in 1978 and 2% in 1979, or $2 million2 in both years. Burundi's major mineral imports in 1978-79 were cement, iron and steel, and refined petroleum products. Abnormal weather conditions, a drop in world coffee prices in 1978, and the conflict in neighboring Tanzania and Uganda in late 1978 and early 1979 combined to re-strict economic growth in Burundi during 1978-79. The gross domestic product (GDP) posted a gain of 6.7% in real terms for 1978 and an estimated 2.5% for 1979 which was significantly less than the 13.7% recorded in 1977, a time of high world coffee prices. The manufacturing and construction sectors were hard hit in 1979 by the conflict between Burundi's eastern neighbors because of transport disruptions which made building materials and manufacturing inputs almost unobtainable.

Jan 1, 1981

Heavy liquids have come into use in ore-dressing investigations, as they make possible the separation of an ore into its specific-gravity components. A paper containing a general dissertation on heavy liquids has been written by John D. Sullivan,4 and the practical application of heavy liquids is explained by Box and Crabtree5. Some heavy liquids become discolored after continued use, and the lack of transparency impairs their value. Since they are fairly expensive, reclaiming is desirable. This paper briefly discusses the preparation and care of some of the more common heavy liquids.

Jan 1, 1928

By Thomas E. Green

A gas volumetric method was developed for determining metallic aluminum at the 0.01-to 0.3-percent level in 100-gram samples of recycled glass. The method is based on the measurement of the change in gas volume produced by the reaction 2 Al + 2 NaOH + 2 H2O ? 2 NaAl02 + 3 H2 using a simple apparatus assembled from readily available glassware. Apart from sampling errors, the precision of the method is within ±5 percent. A minor modification of the apparatus would extend the method to larger samples or samples of higher metallic aluminum content. Metallic iron and metallic zinc do not interfere at the concentrations found in recycled glass recovered from incinerator residues.

Jan 1, 1971