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By Joseph A. DeCarlo

According to the annual survey of beehive-coke plants by the Bureau of Mines, United States Department of the Interior, there were 61 plants with 9,549 ovens in the United States on December 31, 1956, This publication in¬cludes only those for which an annual report was filed with the Bureau of Mines. Not all plants listed were active, however, as nearly one-third of those canvassed were idle all year. A compilation of the returns showed that 44 plants with 6,920 ovens were active part or all year and 17 plants with 2,629 ovens were idle throughout the year. The capacity of beehive ovens has fluctuated between 6 and 14 million tons during the past decade. At the end of 1956, the annual coke capacity of beehive ovens on which reports were received amounted to 5.8 million tons. As noted in table 2, however, not all of this capacity was in operating condition, as 2,093 ovens with a capacity of 1.2 million tons were not operable on [ember] 31, 1956.

Jan 1, 1958

By Martin H. Stanczyk

Freezing to dewater typical Florida phosphate rock slime as demonstrated in laboratory tests appeared to have potential commercial use because of indicated moderate energy requirements, good compaction of dewatered solids, and effective recovery of usable water. After freezing, thawing, decanting, and filtering, batch freezing of gallon-size 13.7 percent solids slime samples yielded 42 percent solids products. Cationic amine, used as a process additive, yielded 46.8 percent solids product with significant filter area reduction. Semicontinuous 8 stage freezing tests also produced thickened slimes. Cooling and freezing 13.7 percent solids slime from 30° to minus 10° C required removal of 183 Btu per pound of slime; Carnot cycle calculation indicated that the theoretical minimum energy to transfer this heat was 27.8 Btu per pound. To produce 1 ton of 44 percent solids slime from 13.7 percent sol-ids slime, the calculated theoretical energy required for cooling and freezing was 52.3 kilowatt-hours. During the research heat capacity and heat of fusion data were determined for the slime at various percent solids.

Jan 1, 1971

By J. Weinberg

This Bureau of Mines report presents data on the changes in the use of steel in motor vehicles over the past 35 yr. Sources of supply of steel for the automotive sector have shifted from almost all domestic in the 1950's to about 50% domestic and 50% foreign in the 1980's. Downsizing, design changes, and substitution of lighter weight materials to achieve energy efficiency also contributed to the market loss of the domestic steel industry. Although plastics and aluminum have displaced some steel in motor vehicles over the years, heavy low-carbon steel is now being replaced most rapidly by lightweight high-strength steel. If the percent of domestic steel used in motor vehicles had not declined since 1950, domestic industry would have supplied 9.3 million more short tons of steel than it supplied in 1985. Downsizing and design changes accounted for 43% of the loss; steel imports, 32%; and substitution of plastics and aluminum, 25%. In 1985, the total value of market share lost by U.S. steel producers was $5.1 billion, of which $1.6 billion was lost to foreign steel producers and automobile manufacturers. Through aggressive marketing and increased efficiency, however, the domestic steel industry may be able to recapture some lost markets, as applications for high-strength steels expand, and as foreign-owned automotive plants in the United States provide fresh sales opportunities.

Jan 1, 1988

By Barry Beith

This report details a study which was designed to assess the effect of retroreflective material on detection and form recognition of workers in the mining environment. Further, the study attempted to determine an optimal configuration of retroreflective material with respect to amount and placement on the body to facilitate detection and form recognition. The study involved a one-fifth scale simulation of the perceptual task found in the underground low seam coal mine. Four different configurations of reflective material were presented in various body positions, common to low coal miners, at three different locations in the visual field, i.e., 10, 25, and 45 degrees from focal line-of-sight. All reflective configurations significantly improve detection and form recognition over configuration (cap only) worn by miners. As the amount of reflective material increased, accuracy also tended to increase. Based on the configurations investigated by this study, the Armband configuration (i.e., refectorized armbands, belt, self-rescuer and battery pack) was determined to be optimum. It is recommended that an actual field evaluation be made using the Armband configuration to establish if simulator results are generalizable to the underground mining environment.

Jan 1, 1980

Research workers from the Bureau of Mines and industry met with other government and industry representatives at the Mont Chateau Lodge, Morgantown, W. Va., on May 30-31, 1973, to discuss the current status of methane control in eastern U.S. coal mines. The opening remarks, the eight technical presentations, and the discussions of the members of a government-industry panel are published here for the benefit of those concerned with the control of methane in coal mines. In addition, an introduction has been added to present the background of work in this field.

Jan 1, 1973

By Frank E. Cash

The iron-ore ranges in the Lake Superior district are the liarquette in Michigan, Menominee and Gogebic in Michigan end Wisconsin, and the Vermilion, Mesabi, and Cuvuna in Minnesota. These ranges produce about 85 percent of the iron ore mined in the United States. Accident experience in connection with this production is better than that of the regions producing the remaining 15 percent. Production and shipments vary slightly from year to year but closely approximate each other over a period of years. During the 4-year period 1940 to 1943, inclusive, 323,667,599 long tons of iron ore was shipped from the Lake Superior district.4/ Michigan and Wisconsin shipped 65,386,608 tons, or 20.2 percent of the total, and employed approximately 15,000 men; Minnesota shipped 258,280,991 tons, or 79.8 percent of the total, and employed approximately 10,000 men. The tons produced per man employed is much, greater in Minnesota than in Michigan and Wisconsin owing to the large open-cut production in Minnesota.

Jan 1, 1945

By Susan M. Moore

Many challenges are faced by workers in lower-seam (42 inches or less) mines. The lower-seam heights confine mine workers to their knees as they perform their daily tasks such as installing roof bolts, delivering supplies, repairing belt, or cutting coal. Miners working in these lower seams often consider kneepads to be their only line of defense against knee injuries. However, healthy knees do not start and stop with kneepads. Other interventions such as changing postures, proper hygiene, and work station design may also be used to reduce mine workers? risks for developing knee injuries. Incorporating these and many other interventions into a mine worker?s ?way of life? is an important step to ensuring a long, healthy career and retirement. Keeping knees healthy is also a key aspect to reducing costs in low-seam mines as the industry battles rising health care costs, and training/recruitment of replacement workers is time-consuming and costly. Educating the workforce about the possible interventions to reduce knee injury risk is a primary objective for the National Institute for Occupational Safety and Health?s (NIOSH) Pittsburgh Research Laboratory (PRL). Therefore, NIOSH researchers, along with industry and academia, developed a training package to educate the mining com­munity about some possible interventions beyond kneepads that may be used to help decrease knee injury rates. Increased awareness and simple changes are the first steps to reducing knee injuries.

Jan 1, 2008

By M. M. Fine

"INTRODUCTION One of the principal activities of the Bureau of Mines during the recent war was to help to increase the supply of strategic and critical minerals. Fluorite was one of the most critical of the nonmetallic minerals because of the increased demand for it as a flux in basic open-hearth and electric steel furnaces and as a raw material for the production of artificial cryolite used in the aluminum industry. Wartime developments in the technology of hydro-fluoric acid, such as the use of the anhydrous acid as a catalyst in high-octane-gasoline production and the use of organic fluorides as carriers for insecticides, also increased the demand for acid-grade fluorspar. 2/ In 1943 the consumption of acid-grade fluorspar was advancing at a more rapid rate than production and was only slightly less than production during the latter half of the year.The outlook for the postwar market for fluorspar is encouraging. Steel production is expected to remain high until the domestic demand for commodities not manufactured during the war is satisfied. The uses for hydrofluoric acid also are expected to increase under the impetus of war-initiated research. In consideration of these and other factors some authorities predict a new peacetime demand for fluorspar equal to 60 to 75 percent of the war production, 5/ 6/ and others believe that the fluorspar industry will be permanently expanded. 7/"

Dec 1, 1947

By D. Harrington

More or less unconsciously and from sheer force of habit human beings do many things they probably would not do if the possible consequences of their acts were fully recognized and appreciated. Such carelessness ordinarily could be condoned if human life were not at stake, but it is difficult to understand why intelligent men engaged in the hazardous occupation of mining indulge with the utmost indifference in some habit or continue some custom in violation of State leas and company regulations and under circumstances that may jeopardize not only their own lives but those of scores, even of hundreds, of their fellow workers as well. The old adage that stolen sweets are the best may or nay not have some foundation, but when applied to the practice of smoking surreptitiously in a coal mine, more especially a gassy mine, it is without even remote justification. Although a relatively harmless habit in the proper environment, smoking has been the cause or suspected cause of many gas explosions and black-powder ignitions and has resulted in numerous instances of bodily injury, loss of life, and destruction of property. Likewise, many fires in both coal and metal nines, causing loss of life, have been started by smoking.

Jan 1, 1941

By C. E. Munroe

In order to meet the emergencies of the world wr, tne quantities of explosivea produced in the Unitecl States, and the number of explosives plants were onti:.1.1.:l,lly ncreased so that when the armistice was declared the Government had on hand larg ..mounts oi militazy explosives in excess of existing military needs. Tle stor3.gs of these explosives entailed a liirge expense and their protection neessitatei the employment of m'3.l'lY men who could be better employed otherwise in the military estlish.11ent. Moreover, mar.y ex.ploives, like QJ.l other material, deteriorate on prolonged storage, They lose tht precise definiteness of properties and behavior on which reliance· is placed in military operations, The continued expen3e and d3.nger ttending storage of theae explosives might be diminished by dcst1et1on of the surplus beyond immediate needs, but such·deetniction is danger• ou5 qnd coetly. Hence, the evident solution o! the problem was the salvage d prompt ut111zation of the ru.rplua •

Aug 1, 1922

By A. B. Hooker

[Permissible electric cap lamps represent a workable balance between the amount of light needed and the various limiting conditions, such as the weight the miner can carry conveniently, cost of the lamp, including upkeep, and adequacy or practicability of the lamp as regards safety, mechanical strength, and general performance. Other things being equal, the coot desirable lamp is one that gives the greatest amount of useful light. Conversely, with a given amount of light the most desirable lamp is one that its the most efficient respecting weight, cost, and performance.]

Jan 1, 1935

By A. B. Hooker

[Permissible electric cap lamps represent a workable balance between the amount of light needed and the various limiting conditions, such as the weight the miner can carry conveniently, cost of the lamp, including upkeep, and adequacy or practicability of the lamp as regards safety, mechanical strength, and general performance. Other things being equal, the coot desirable lamp is one that gives the greatest amount of useful light. Conversely, with a given amount of light the most desirable lamp is one that its the most efficient respecting weight, cost, and performance.]

Jan 1, 1935

By James S. Browning

Heavy liquids have been used to separate minerals of different specific gravities for many years.4 5 6 7 8 9/ The method permits substantially quantitative evaluation of a variety of minerals and requires much less time than the usual methods of chemical analysis. This Bureau of Mines investigation was conducted to determine the applicability of heavy liquid mineral separation to the evaluation of certain spodumene and kyanite ores, prepared mixtures, and plant products. After careful standardization of the particular mineral and associated gangue, estimates of chemical analyses could be obtained from results of heavy liquid separations.

Jan 1, 1960

By John A. Organiscak

Enclosed cabs are a primary means of reducing equipment operators? silica dust exposure at surface mines. The National Institute of Occupational Safety and Health recently performed a laboratory study to evaluate which factors on an enclosed-cab filtration system are most significant. The various factors evaluated were intake filter efficiency, intake air leakage, intake filter loading, wind infiltration, use of a recirculation filter, and the use of an intake pressurization fan. The result of this laboratory testing has shown that the two most important factors for an effective filtration system on an enclosed cab were the efficiency of the intake filter and the use of a recirculation filter. A higher-efficiency intake filter considerably increased the quality of the intake air that was delivered into the enclosed cab. It also was determined that air leakage around the intake filter notice-ably reduced its air cleaning effectiveness. The second key factor is the use of a recirculation filter, which was shown to improve the air quality in the enclosed cab by six to 12.7 times more than the intake filter alone. The reason for the significant improvement was that the cab air was constantly drawn through the recirculation filter, thus continually filtering the dust out of the air.

Jan 1, 2010

By Arnold J. Farstad

The Location Group conversed in the Petroleum Room of the Green Center with the purpose of addressing the following list of topics in light of the Bureau of Mines' requirements for detecting and locating trapped miners by electromagnetic methods. These topics include: Noise, Sources, Antennas (transmit and receive), the Propagation Medium, Signal Processing, Optimum Frequency, Receivers, Pulse vs. CW Techniques, Passive Location Techniques, and Obstacles. Practical constraints such as equipment size, weight and power requirements, cost and intrinsic safety were kept in mind during these discussions. It was emphasized that in-mine equipment must be inexpensive, rugged, simple and lightweight. Otherwise, the mine operators probably would not buy it nor would the miners be able to effectively use it. Present techniques for experimentally detecting and locating trapped miners were discussed, along with techniques to improve their location accuracy. Analytical, numerical, and scale modelling methods were considered as a means of giving further insight into measurement, anomalies caused by terrain variations, conductivity contrasts, and obstacles. After discussion of these topics, conclusions were drawn and existing problem areas were identified. These problem areas were addressed in developing guidelines for future efforts. Following the discussion period, the Chairman gave a summary of the Location Group report and comments were solicited from the entire group. 2.0 GROUP DISCUSSION HIGHLIGHTS 2.1 Noise W. Bensema asked the group whether the noise data provided by NBS was adequate. It was determined that for location systems analysis, the most important form of noise data was the frequency spectra of vertical and horizontal magnetic fields on the surface, and the answer to his question was affirmative. Drs. Wait and Frischknecht pointed out the difficulty in accurately measuring the true vertical magnetic field since these measurements are heavily influenced by the loop setting and the local geology. Nevertheless, these measurements are important since the same perturbations would also affect a receiving loop oriented to receive the vertical magnetic field. Dr. Rankin pointed

Jan 1, 1973

By Joseph J. Wallace

1. The Pocahontas No. 3 and Pocahontas No. 6 ere the two most important beds in Mercer County from the standpoint of present production and recoverable reserves. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and 1,800 tons per acre-foot of coal in place, are estimated at 188 million short tons as of January l, 1953. Of this total, 80 million short tons are in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager to make an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1954

By A. J. Kraemer

[A great deal of interest has been manifested in the question of sulphur in fuels for automobile engines. Many different opinions have been expressed with respect to the effect of sulphur in gasoline on engine wear and engine performance. A wide difference of opinion exists as to the permissible limit of sulphur content for satisfactory operation.]

Jan 1, 1927

By Albert E. Keller

This paper describing the timekeeping and pay-roll methods of the Britannia raining and Smelting Co. (Ltd.) is one of a series being prepared for and published by the United States Bureau of nines regarding office procedures in connection with mining operations. The general office of the Britannia Mining and Smelting Co. (Ltd.) is located at Britannia Beach, B. C., a town of about 600 inhabitants at tidewater on the east side of Howe Sound and about 30 miles from Vancouver, B. C. The Beach, as it is locally termed, is a company town consisting largely of about 250 employees of the company and their families. Here is the milling and concentrating plant of over 6,000 tons daily capacity- the main service units comprising the electrical, mechanical, blacksmith and woodworking shops and the local electric-furnace foundry; the central-heating steam plant; the air and electric generating units; the ball-manufacturing plant; the warehouses; and the general store, which serves this community and also acts as distributor for the general stores located elsewhere on the property.

Jan 1, 1932

Reduce worker exposure to respirable dust without interfering with bag-filling operations. Approach A dust control hood was developed which contains and captures dust close to its source and prevents it from entering the bag-filling operator's work place. How It Works A sheet metal hood is placed around the nozzle of the bag filling machine. The hood is connected through ducts to the plant exhaust ventilation system. Air pulled into the front of the hood and around the sides of the bag picks up dust generated inside the hood, and carries it to the dust collector. The size of the hood can be adapted to fit most fluidized valve-type bag-filling machines. The height of the hood depends on the bulk density of the product and weight of the bags being filled. The 14-inch-width of the hood allows it to be used on multi-nozzle baging machines spaced 16 inches on center. Only 2/3 of the bag is actually within the hood, and this allows easy operator access for placing the bags on the nozzle.

Jan 1, 1978

By S. J. Davenport

[The tremendous increase in mine mechanization since 1929 has increased markedly the application of electric power in and about the coal mines of the United States. Cutting, drilling, and leading machines have replaced hand-mining methods in nary mines. As a result, expansion of the gathering haulage has necessitated introduction of extensive feeder, trolley, grid other power wires. (1)3/ In spite of this vast mechanization the fatality rate from electric shock has been on the decline. However, there are still too many accidents, and efforts to eliminate electrical hazards cannot be relaxed. It is hoped that an acquaintance with the physiological aspects of electrical accidents will make workers end management aware of the lurking dangers of this very common and extremely dangerous form of energy.]

Jan 1, 1951