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By Doerner H. A.

From thermodynamic calculations Maier predicted that zinc oxide and methane would react at specified temperatures substantially according to equation (1). (1.) ZnO + CH4 = Zn (gas) + CO + 2H2. Other reactions that may take place are (2.) CH4 = C + 2H2. (3.) ZnO + CO = Zn (gas) + CO2. (4.) ZnO + H2 = Zn (gas) + H2O. Maier predicted that 870°C would be the critical temperature above which reaction (1) would take precedence over reaction (2) and that reaction (1), at equilibrium, would be substantially complete at or above 927°C. Theoretical considerations indicate that reaction (1) is reversible: this is supported, but not proved, by experimental data. The other reactions are known to be reversible. At low temperatures reaction (2) requires a catalyst and it is slow below 1000°C. Reactions (3) and (4) are rapid, but the equilibrium constants are such that only small concentrations of CO2 or H2O can be produced below 1000°C. Maier calculated that CO2 should not exceed 0.5 per cent at 870°C., and the calculation for water vapor gives a still smaller order of magnitude.

Jan 1, 1931

By Donald E. Redmon

This Bureau of Mines report reviews injury experience in the metallic mineral industries for 1966-67. For each of the years, 27 tables summarize disabling work injuries by department, source of injury, extent of disability, part of body injured, and nature of injury. Correlative information on employment, worktime, and operating activity is also presented.

Jan 1, 1973

By Donald E. Redmon

This Bureau of Mines report reviews injury experience in the nonmetallic mineral industries (except stone and coal) for 1968-69. For each of the years, 23 tables summarize disabling work injuries by department, source of injury, extent of disability, part of body injured, and nature of injury. Correlative information on employment, worktime, and operating activity is also presented.

Jan 1, 1973

By Thomas M. Barczak

The U.s. Bureau of Mines is conducting research to optimize the utilization and design of mine roof support systems. This report describes methods to evaluate resultant loading on longwall shields, defined as external resultant vertical and horizontal force acting on the canopy and base. Four models are considered: two rigid-body models, an elastic model, and a numerical model. The rigid-body models equate measured internal shield forces to unknown external resultant shield forces (loads) through rigid-body analysis of static equilibrium requirements. The elastic model develops a solution to shield mechanics by evaluation of the load-displacement relationship and stiffness characteristics of the support structure. The numerical model is a two-dimensional finite-element representation of a shield structure. Model determination of resultant shield loading is compared to controlled loading of a shield in the Bureau's mine roof simulator. Parameters investigated are shield height, canopy contact configuration, canopy and base horizontal constrainment, and boundary conditions imposed by vertical and horizontal shield displacements. It is concluded that rigid-body models are most applicable to in situ measurement of shield loading. Applications requirements and potential error sources are discussed.

Jan 1, 1990

By John P. Conway

This Bureau of Mines investigation was undertaken to determine the feasibility of lock-bolt support in Tertiary-gravel material. Pull tests were performed on five types of rock-bolt anchors to determine their optimum anchorage capacity. Four of these anchors are commercially available; the fifth, an explosive-anchor bolt, was developed by the Bureau of Mines. To increase anchorage capacity, epoxy grout was used with several of the commercial types of bolt. Tests showed that sufficient anchorage could be obtained by employing epoxy-resin grout with the commercially available wedge bolt, or by using the explosive-anchor bolt. Also estimated are bolt spacing and cost of a rock-bolt support system.

Jan 1, 1971

By Wm .. W. Odell

There is outlined below the essential facts brought out in an investigation into the causes for emulsion difficulties as experienced at many water gas plants . The investigation was conducted under a cooperative agreement between the University of Illinois Engineering Experiment Station , the Illinois State Geological Survey , and the U. S. Bureau of Mines . Funds of the Illinois Gas Association were used to defray a part of the costs . Active assistance was rendered by the Peoples Gas Light and Coke Company , of Chicago , who furnished a laboratory at Chicago for conducting the experiments , and loaned the services of Mr. E. A. Thiele to help with the laboratory work . A full report on the results of this work will be published by the Bureau of Mines later but it is believed desirable to bring the principal results now to the attention of the industry . In almost every gas plant where carbureted water gas is made , some difficulty is experienced , at one time or another , in separating the tar fran the water that condenses from the gas . The fact that annoyance from this source is ever present in some plants , and seldom present in others , leads to the belief that certain operating variables have considerable to do with the formation of difficulty separable tarwater emulsions . Accordingly , when samples of tar were collected for laboratory study , the operating conditions and methods were simultaneously observed and recorded.

Mar 1, 1922

By Theodore Kootz

Manufacture of high-grade ferromanganese; as a rule; requires a low-phosphorus-manganese ore with 45 to 55 percent Mn, chiefly obtained in the Soviet Union, the British Dominions, and Brazil. Also, low-manganese ores have already been used for ferromanganese production, especially in North America .and Germany. During World War I, a process was developed in which a high-phosphorus ferromanganese or spiegeleisen was prepared in the blast furnace from law- or high-phosphorus manganiferous ores, then low-phosphorus manganese slag was prepared by refining under an acid slag, and this material was, worked into a low-phosphorus ferromanganese in the blast furnace.9/ Manufacture of useful manganese ores from a phosphorus-bearing spiegel with 12 to. 15 percent Mn, 4.5 percent C,, and 0.5 percent P by slagging in a refining furnace was reported by Joseph, Barrett, and Wood.10/ The spiegel was refined to 0.75 percent Mn, 3.4 percent C, and 0.45 percent P. Thereby, a slag with about 43 to 58 percent Mn and, about 10 percent Si02, was obtained. Hotter melts gave a smaller phosphorus content in the slag than cold melts. In addition, the phosphorus content of the slag varied with the manganese content of the intermediate metal.

Jan 1, 1952

By C. Lorimar Colburn

"The use of helmets during the war has accentuated interest in the advisability of using stiff hats in mines to protect the miners against falling rocks. About forty per cent of the accidents in mines are due to falling rocks or roof. A large number of these accidents could be prevented if the miners wore stiff hats or helmets.The use of head protective devices in minas is not new, for they have been in use for many years in Europe and in the Lake Superior District in the United States. In practically all of the mining districts in Europe stiff hats of some kind are required by the mine management. George S. Rice, chief mining engineer of the Bureau of Mines, reported that in Germany, Belgium, and France stiff hats made of papier mache or felt rosin are in use. Similar hats are generally employed in the Lake Superior District. In building the subways of New York and Philadelphia it was the practice of engineers and workers to let the hair grow very long and to wear a close fitting cap or felt hat. In Germany the hats are high like the military helmets, whereas in France and Belgium they fit more closely to the crown. In England the practice is mixed. As a rule the miners use soft padded caps, but in Yorkshire many of the miners use sole leather, tight-fitting caps of jockey pattern with the seam forting a little ridge down the middle of the cap. These hats are very useful allow thin beds of coal, as in crawling one is very likely to strike his head a sharp piece of rock or on a timber. Of course, such mishaps are more likely to occur to a man not familiar with the mine. It must be admitted such hats do not stick on well, though this is usually due to their not being especially fitted. The German hat is particularly unsuited to an American-shaped head.It is interesting to note that on the continent tight cotton caps are generally worn over the hair and under the hard hat. This is a measure for cleanliness which is excellent. In low beds of coal share much crawling on hands and knees is necessary the dirt and coal dust sift down, making the miner black and dirty. In metal mines stiff hats are of especial use in shaft work; also in raises or high stapes. A small fragment of rock falling some distance either down a shaft or raise would kill a man if it struck him squarely on the head. A stiff hat or helmet may protect him and save his life. At a station in a shaft where men are loading the cage or skip, some kind of adequate head protector should be compulsory. A head-protecting hat or cup which is also a good insulator should be worn where there is danger of striking one's head against a wire carving an electric current."

Jun 1, 1920

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 Arthur L. Murray

The first thought in the case of an accident or contagious disease is naturally that aroused by our humane instinct , how serious is the case and will the person recover ? The economic effects of such cases , owing to their many ramifications , are seldom realized either by those directing mining operations or those engaged in the labor of producing . This paper is based on the accident experience of the State of Utah and the number of cases of two well known preventable diseases , typhoid fever and smallpox , in that State for the fiscal years 1917-1918 , 1918-1919 , 1919-1920 , and 1920-1921 . The data and figures presented are from coal -mining camps only . W. W. Adams , mine- accident statistician of the bureau, contributed valuable corrections and suggestions . The economic results of accidents are considered first , and those of the two preventable diseases later .

Apr 1, 1922

By Cheryl Hill, Michael Keane, Pamela Mike, Raghoottma Pandurangi, William Wallace, Mohindar Seebra, Val Vallyathan

"Dipalmitoyl glycerophosphorylcholine (lecithin) dispersed in physiologic saline, a model of the primary component of pulmonary surfactant, is adsorbed by respirable quartz and aluminosilicate dusts. Dust cytotoxicity as measured by erythrocyte bemolysis and pulmonary macrophage enzyme release is suppressed by this adsorption. The degree of suppression of hemolytic potential versus specific adsorption of lecithin from dispersion in saline by respirable quartz and kaolin dusts are compared with dusts' BET specific surface areas to interpret the prophylactic effect of lecithin adsorption. Dust hemolytic potential versus medium pH is presented. Fourier transform infrared spectroscopy and photo-acoustic spectroscopy of lecithin on quartz and of lecithin on kaolin are presented and reviewed with results of studies of the time course of removal of lecithin adsorbed on mineral surfaces by digestion by phospholipase enzyme. Results are discussed in terms of a model of prompt neutralization of respired mineral dusts by pulmonary surfactant, and a gradual re-toxification by digestive processes acting on the adsorbed prophylactic surfactant coating following phagocytosis. INTRODUCTIONQuartz dust of respirable size is well known to cause fibrotic lung disease, but numerous questions persist in the understanding of the initiation and progression of this disease. Our approach concentrates on physical and chemical aspects of mineral dusts early-on in their interactions with living organisms, and we have chosen simplified models to investigate that interaction.In the alveolar ·spaces of the lung, tissue is coated with a surface-active material (pulmonary surfactant), which, among other functions, mechanically stabilizes the lung from collapse by reducing the surface tension of water in the alveolar sacs.1 This surfactant is also the material that is first contacted by a mineral particle that is transported to an alveolus and is impacted there. This surfactant material has been studied extensively. The primary components are known to be proteins (about 11 % in dog lavage fluid), and phospholipids (about 88%).2 Pbosphatidyl cholines constitute roughly 80% of the phospholipid fraction; about 70% of the phosphatidyl choline fraction is dipalmitoyl lecithin (DPL).2 Respirable aluminosilicate particles are capable of adsorbing dipalmitoyl lecithin from dispersion in physiologic saline, a model for a possible initial event occurring upon deposition of a particle in a pulmonary alveolus. As may be seen from Figure 1, the DPL molecule has several fixed charges at neutral pH; a positive charge on the trimethylamine (choline) moiety, and a negative charge on the phosphate group. Also evident are the two fatty acid residues of palmitic acid, which are bonded through ester likages to the glycerol segment of the molecule. The fatty acid moieties of phosphatidyl choline make the molecule inso1uble in aqueous solutions under normal conditions, but a colloidal unit of aggregated molecules called a micelle is usually formed spontaneously above a certain minimum concentration. Small micellar vesicles are generally formed in the laboratory by using ultrasonic agitation or by solvent evaporation methods."

Jan 1, 1990

By F. S. Crawford

Safety devices and guards are often looked upon as the last word in safety by the men around the shop or large industrial plant . However , thorough knowledge of the details of their jobs and of the dangers attending them are even more important . It should be unnecessary for all men to go through the experience of the first man to meet an unknown danger , but that appears to be about the only way by which many learn . Practically every danger connected with the job around a mine , blast furnace , steel mill , foundry , coke oven , cement mill , or other operation , was encountered for the first time by someone , and if he was fairly fortunate he either got hurt or just missed being injured and lived to tell his " budaies " how it happened; he spread the knowledge of that particular danger . Sometimes , but not often , a man can foresee a danger . If he could always be on guard and remember everything he had ever learned and also know everything that had happened to the other fellow , and then let that knowledge keep him aware of the dangers in his own immediate " job , " so that he would work the safe way for both himself and the other fellow , he would have what safety engineers call " safety consciousness . " Being safety conscious is a fine attribute , as it really means knowing all about one's job . A man who is really safety conscious is one of the best and most efficient workmen in the whole plant . The boss wants men of that kindmen who want to learn and who try to learn every little detail about their jobwhere there is danger of spoiling the heat or getting burned by hot metal in a steel plant or of loading rock instead of coal or ore in a mine . Such men know how to do whatever job they are on easily and with the least amount of hard work and at the same time get it done as quickly as possible with safety . A man who is safety conscious has to nearly all intents and purposes developed eyes in the back of his head , if he is in a big mill where there if something going on all around him . These eyes are not real eyes , but they are what might be termed a sixth sense which he has developed by his experience in the mill as well as in other dangerous work which he may have done before in other plants . There may be occasions when a man's safety consciousness will leave him for just a short time ; this is likely to happen when he is thinking about a quarrel he had with his wife which has not been cleared up happily , or perhaps when he has bought too many things on installment and with sickness at home

Apr 1, 1931

By J. M. Stuve

The present Bureau of Mines investigation measured low-temperature heat capacities of NiBr2 (8 to 302 K) and NiS04 (9 to 70 K) by adiabatic calorimetry. The standard entropies (S°, 298.15 K) of NiBr2 and NiS04 were calculated as 29.26 ± 0.06 cal/deg mole and 24.21 0.04 cal/deg mole, respectively. (1 cal = 4.1840 joules.) Heat-of-solution measurements of anhydrous NiBr2 were used to determine its enthalpy of formation (?Hf°, 298.15 K) as -50.64 ± 0.31 kcal/mole. High-temperature enthalpies of NiBr2 and NiS04 were measured by drop calorimetry to 1,150 K and 1,002 K, respectively. Enthalpies, heat capacities, and related formation functions are tabulated to 1,200 K.

Jan 1, 1978

By J. W. Walkiewicz

The Bureau of Mines investigated alloys containing lanthanum (La), praseodymium (Pr), neodymium (Nd), cobalt (Co), copper (Cu), iron (Fe), and magnesium (4g) as possible components of a permanent magnet mate¬rial utilizing a cerium-free synthetic mischmetal (M) as a substitute for scarce samarium (Sm) metal. Magnets containing M-Co-Cu-Mg and M-Co-Cu-Fe-Mg were fabricated by powder metallurgy techniques and evaluated. A synthetic mischmetal (M20) containing 20 pct La, 60 Pr, and 20 Nd yielded the best overall magnetic properties. The M20-Co-Cu-Mg alloys had energy products as high as 13.2 MGOe, remanences as high as 7.89 kG, normal coercivities as high as 6.26 kOe, and intrinsic coercivities as high as 13.4 kOe. The best value of intrinsic coercivity, 22.9 kOe, was obtained with an M-Co-Cu-Mg magnet in which the synthetic misch¬metal contained 30 pct La, 50 Pr, and 20 Nd. These values compare favorably with those of the Sm-Co magnets fabricated and measured at the Bureau's Reno Research Center, which had energy product of 15.1 MGOe, remanence of 7.8 kG, normal coercivity of 7.5 kOe, and intrinsic coercivity of 27.4 kOe. Iron substitution for part of the cobalt resulted in a decrease of magnetic properties, although several percent iron can be added before a drastic loss of magnetic properties occurs.

Jan 1, 1983

By Noel N. Moebs

The coal wants at the Westland Mine in southwestern Pennsylvania consist chiefly of elongated, sandstone-filled channels with slickensided basal contacts. Tentatively identified as washouts, these channels are about 1,000 feet long and 300 feet wide, are erratic in occurrence and trend, and are difficult to delineate from the customary core drilling pattern. Roof conditions are hazardous adjacent to the washout contact, but roof stability is generally unaffected greater than 30 feet away.

Jan 1, 1981

By H. A. Doerner

From thermodynamic calculations3 Maier predicted that zinc oxide Land methane would react at specified temperatures substantially according to equation (1). (1) ZnO + CH; = Zn (gas) + CO + 2H2 Other reactions that may take place are: (2) CH4 = C + 2H2. (3) ZnO + CO = Zn (gas) + CO2 (4) ZnO + H 2 = Zn (gas) + H2O . Maier predicted that 870°C. would be the critical temperature above which reaction (1) would take precedence over reaction (2) and that reaction (1), at equilibrium, would be substantially complete at or above 927°C.

Jan 1, 1931

By L. G. Marshall

This report, describing the mining method of the Dresser Trap Rock Co., Dresser, Wis., is one of a series published by the Bureau of Mines on mining methods, performance, and costs at mining operations throughout the United States. SUMMARY Dresser, in Polk County, is 3 miles south of St. Croix Falls, Wis. Company operations are about 1 mile north of the townsite. The mine has been in [peration] since 1914 and under the present ownership since 1949.

Jan 1, 1959

By R. E. Head

[This paper embodies the data obtained by a detailed statistical, microscopic analysis of the composite mill feed concentrate, and tailing from the Magne and Arthur mills of the Utah Conger Co. for 1 month in 1929. It is one of a series of papers by the same authors5 dealing with the mineralogical characteristics of the ore and concentration products from various well-known plants. The work was done in the cooperateive microscopic service laboratory at Salt Lake and represents the results of cooperation between the United States Bureau u of Mines, the Utah Copper Co. and the University of Utah.]

Jan 1, 1935

By R. E. Head

This paper embodies the data obtained by a detailed statistical, microscopic analysis of the composite mill feed concentrate, and tailing, from the Magne and Arthur mills of the Utah Conger Co. for 1 month in 1929. It is one of a series of papers by the same authors dealing with the mineralogical characteristics of the ore and concentration products from various well-known plants. The work was done in the cooperative microscopic service laboratory at Salt Lake and represents the results of cooperation between the United States Bureau of Mines, the Utah Copper Co., and the University of Utah.

Jan 1, 1935

By Rimas Pakalnis, Catherine A. Dreesbach, Lewis A. Martin

Instrumented cable bolts developed at the Spokane Research Laboratory of the National Institute for Occupational Safety and Health were used in conjunction with existing ground control systems to monitor rock mass loads at Tg Soda Ash's trona mine, Granger, WY. Axial and shear loads were determined to levels of strain gauge accuracy of ±5 N or ±5 micro strain. These gauges were embedded in a remanufactured king wire that replaced the conventional king wire. Cable bolt performance, quality of grout, and installation techniques were also assessed. By using instrumented cables, a mine operator can determine axial load along the cable at predefined gauge locations. These data provide necessary input for an operator to design a safer working environment for miners.

Jan 10, 2000