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By Leslie H. Sharp, Martin J. Gavin

Those of the oil-shale operators in this country who are sincerely attempting to make a real industry out of oil-shale developments, are anxious to obtain fundamental data on the retorting of oil-shale; particularly as regards the effect of certain variable factors in the process of retorting on the quantity and quality of products yielded from oil shales when they are subjected to destructive distillation. From careful examination of a con siderable number of suggested processes for treating oil shales and the con flicting ideas on which they are designed, it seems probable that accurate information of a fundamental nature is highly essential to the successful establishment of an oil-shale industry in this country. . Accordingly, the United States Bureau of Mines, in cooperation with the State of Colorado, is undertaking to furnish some definite and impartial information of this type through investigations now under way at the University of Colorado, Boulder, Colo. A retort for the distillation of oil from oil shale has been designed and installed, together with the necessary auxiliary equipment for controlling and determining variable factors of distillation, and for recovering and de termining the quantity and quality of the products yielded from the shales. The retort is of such a nature that conditions of retorting can be accurately . and completely controlled, and varied at will. It is not designed as a com mercial retort, but only for research purposes. A testing laboratory with equipment necessary for the examination of the shales, physically and chemic ally, and the products yielded by them, has also been fitted up . The material used in the investigations is oil shale obtained from the DeBeque, Colorado, shale field. It yields on distillation in the Bureau of Mines testing apparatus, about 42 gallons of oil to the ton, and is there fore a fairly representative sample of the shales that probably will be first worked in Colorado. The shale used will be as uniform as possible in character and oil yield and will all be obtained from the same seam at the same point, in order to avoid the introduction of unnecessary variable factors in the tests and to render results strictly comparable •

Jul 1, 1920

By L. H. Banning

This investigation was undertaken to obtain basic information necessary for the design and operation of a plant for recovering metallic values from nickeliferous laterite and serpentine of the Philippine Islands. It was divided into three parts: (1) Mineralogical studies and preliminary mineral dressing tests; (2) electric smelting of the ores, upgrading of ferronickel by blowing with oxygen, smelting laterite slag to produce crude iron, and the production of mild steel; and (3) nickel and cobalt recovery from upgraded ferronickel. Results of the investigation indicate that it should be feasible to recover nickel, iron, and possibly cobalt products from the laterite and ferro-nickel from the serpentine. Mineralogical studies were made on representative fractions of the laterite and serpentine tonnage samples and on five selected samples; mineral dressing tests were made only on laterite. The nickel occurs principally associated with hydrous iron oxides and chemically combined with serpentine; garnierite was the only discrete nickel mineral identified, and it was found in a highly decomposed serpentine. The bulk of the cobalt was found in wadlike manganese oxide material. Approximately twice as much chromite was found in the laterite as in the serpentine, By mineral dressing techniques, laterite was separated into two fractions: one fraction contained over 90 percent of the nickel and cobalt, and 83 percent of the iron; the other fraction contained 74 percent of the chromium. A cobalt concentrate (1.1 percent Co) was produced by a scrubbing and sizing procedure.

Jan 1, 1962

By J. H. East, D. Harrington

Fires in metal mines have resulted in some of the worst disasters in American mining history insofar as loss of life is concerned. One fire caused the death of 163 miners and individual less spectacular fires have cost the lives of scores of workers. Metal mines are often very deep, and the men working on numerous levels far removed from direct communication with the surface. In many instances they cannot be warned quickly of an emergency or a mine fire by telephone or other usual method of communication, or by messenger, flashing lights, gongs, sirens, or whistles. Telephones are not paricularly effective as a means of warning unless placed at all strategic points and with attendants always on duty; though telephones well placed have a definite value in any well-pla.mied emergency procedure in mines of all kinds. Messengers are slow and men working in remote parts of a mine would not receive a warning quickly enough. Most metal mines are not electrically lighted, except at or adjacent to shaft stations and in principal haulageways, and this limits the effectiveness of flashing lights. Electric gongs and sirens or whistles have been tried as warning signals, but the sound is quickly deadened and does not travel upward into the stopes, especially those of an extensive volume. Shutting off the compressed air is by no means satisfactory as a warning, as not infrequently it is stopped accidently, so that it loses its value as an alarm. The introduction of water into compressed air lines is undesirable as a fire warning and necessitates considerable care, especially in deep mines; pressure-reducing valves must be provided to reduce pressure that otherwise would break connections or split the pipe. A quick, effective method of warning miners underground of the existence of an emergency requiring them to leave the mine immediately, such as a fire on the surface or underground, is provided by the introduction of stenches in the compressed-air lines. This method of warning is by no means experimental, inasmuch as it has been used successfully for many years in

Jul 1, 1943

By F. E. Block, T. T. Campbell, D. Z. Hobbs

Several methods were investigated for the preparation of high- purity elemental boron in an attempt to develop a feasible process for producing boron on a large scale . In the work described in this report , the metal was prepared by metering boron trichloride gas into a crucible containing molten metal reductants . It was necessary to remove reaction byproducts by acid and aqueous leaching . Magnesium and sodium were tested as reductants , but best results were achieved using lithium or zinc as reductants . Contaminants originating from the materials of construction were the chief impurities in boron made by this method . Impurities ranged from 0.5 to 5.0 percent . Impure boron ( 85 to 90 percent ) was also prepared by the magnesium reduction of boron trioxide in a thermite - type reaction . This product contained magnesium as the chief contaminant . Impure boron made in this way could be upgraded by fusing with potassium fluoborate or potassium acid fluoride . After acid leaching the fusion cake , a product containing 95 to 97 percent boron was obtained . Analytical techniques for accurate determination of impurities in elemental boron are a major problem , requiring solution before a valid comparison can be made of the quality of boron prepared by these various methods .

Jan 1, 1964

By A. L. Murray

First -aid training as an adjunct to safety is receiving more wide spread recognition in the industries every year . Moreover , the adoption of a program for giving firstaid training to practically all employees at a mine or plant is based upon the experience gained and good results obtained from standard first -aid instruction during the past two decades . In the near future industries that desire to maintain a low accident rate , to decrease compensation costs , to reduce lost time , and to build up an efficient , loyal working force , will recognize that training in first aid is one way of attaining these results with little expenditure of time and effort . Progressive organizations will require every man from the superintendent down to take first - aid training and not , as heretofore , only a small percentage of the working force . When employees learn that first - aid training can be applied not only at their daily tasks but in their homes and on tthhee highways ,, they will welcome the opportunity of learning how to care for injuries and perhaps save lives . In a limited way first - aid instruction was given to miners as early as 1899 . Later , in 1904 , a few of the companies in the Pennsylvania anthracite district inaugurated the distribution of first - aid packets to their employees and instructed them in the use of the contents . It remained , however , for a branch of the United States Government to grasp the real significance of widespread first - aid training as an effective means of saving life and minimizing suffering from the large number of accidents among workers in the mineral industries . The United States , owing to its vast resources , both natural and human , for

Jan 1, 1930

By C. G. Maier

Relatively infrequent use by metallurgists of the term "sponge chromium" as contrasted to more than occasional reference to "sponge iron" may be ascribed to the fact that the former material is not a commercial product, while the latter has been known and used, at least in one form (Swedish sponge iron), for several decades. It is doubtful whether a true sponge chromium ever has been prepared heretofore in the laboratory by more than one or two investigators. Nature presents a much. more difficult problem to the investigator endeavoring to make sponge chromium than pertains to the production of more easily reducible elements such as iron or nickel. Recent widespread interest among metallurgists in the possibilities of powder metallurgy is ample incentive to explore the feasibility of producing pure chromium metal in finely divided form. The shift in terminology of this statement from "sponge" to the "finely divided form" is deliberate in emphasis of distinction between terms that occasionally have been used loosely. It would seem desirable that a uniform usage descriptive of finely divided metals be adopted. While to some it might seem preferable that the terra "powdered" metal be reserved for a finely divided form produced by mechanical means, as, for example, chromium produced by the mechanical comminution of electrolytic sheets or flakes, current usage of the term "powder metallurgy' involves no distinction as to source type of material. It is usually accepted, however, that a sponge metal is one reduced from oxide or other combined form at temperatures below the melting point of metal or oxide so that the particles of metal are pseudomorphic, at least macroscopically, with the source material, and, in consequence of the loss of material without change of external shape of the particles necessarily have an open, porous, or "spongy" structure.

Jan 1, 1942

By William N. Hale

This Bureau of Mines report gives a detailed study of water usage in the Montana mineral industries, along with projections for the future. The mineral industry of Montana in 1963 used 36.5 billion gallons of new water, and reused or recirculated an additional 53.5 billion gallons for a total water requirement or usage of 90 billion gallons. The petroleum industry was the major water user, followed by the copper and zinc industries. Many mineral industry operators provide their own water, and new water is withdrawn largely from surface sources. At present, sufficient water is available in rivers, streams, and reservoirs in Montana; however, shortages do exist locally near mineral industry operations using large quantities of water. Some is supplied from sources up to 44 miles distant. New water withdrawn by the State of Montana mineral industry is expected to increase from 36.5 billion gallons in 1963 to 51.1 billion gallons by the year 2000. The total-water requirement is expected to more than double, or reach 182 billion gallons by the year 2000.

Jan 1, 1966

By Robert E. Barieau

General expressions for evaluating various thermodynamic properties applicable to the van der Waals equation of state have been derived. These formulas were subsequently used to evaluate various thermodynamic functions in the two-phase region. The results indicate that, for a van der Waals fluid, there is a finite discontinuity in the second derivative of the vapor pressure curve, in the second derivative of the chemical potential or Gibbs free energy at the critical point, and in the heat capacity at constant volume measured at the critical density. Numerical values are tabulated and graphs are presented for all functions calculated.

Jan 1, 1967

By Michael A. Trevits

During the time period from 1990-2007, there were 1601 reportable fires that occurred in the U.S. mining industry (an average of 89 fires per year). The leading causes of U.S. mine fires include flame cutting and welding operations, frictional heating and ignitions, electrical shorts, mobile equipment malfunctions, and spontaneous combustion. The National Institute for Occupational Safety and Health (NIOSH) is conducting a program of research addressing metal/nonmetal and coal mine fire prevention, detection, management and suppression. In the metal/nonmetal area, work was focused on technology transfer and training, and research to reduce the number of mobile equipment fires and their hazards. In the coal arena, research is underway to determine the root cause of cutting and welding-related fires and to evaluate the effects of ventilation schemes relative to the spontaneous combustion risk in longwall mines. Relative to fire management, research is ongoing on remote mine seal installation and remote mine fire suppression technologies. Finally, research is continuing to develop comprehensive and usable smoke management techniques and to develop mine fire growth models, propagation, and suppression. This paper presents a summary of some of the mine fire research and provides an overview of the next phase of the NIOSH mine fire research program.

Jan 1, 2010

By W. C. Smith

This Bureau of Mines report discusses how pull-test data can help establish polyester resin column length criteria for roof bolts in evaporite minerals. The study evaluates the effectiveness of partial to full columns of resin in anchoring 4-ft, No.6, grade 40 rebar roof bolts in potash, salt, trona, gypsum, and borate mine roofs. Pull tests were performed on over 600 roof bolts in 11 evaporite mines. Column lengths ranging from 6 to 48 in (fully grouted) were evaluated for each test site. In general, comparative results among all test sites indicate that pull-out loads in excess of 10 tons (force) were attained with resin-grouted bolts having 13 to 75 pet less than a full column of polyester resin. Ten tons (force) of load-carrying capability compared favorably, in terms of strength, with the calculated yield strength of the rebar used in the tests, which was 8.8 tons (force). The site-specific nature of each test site, due to the unique combinations of geology, mine-induced stresses, and other unknown parameters, prevented the establishment of valid generic column-length criteria. For these reasons, data to evaluate resin-column-length effectiveness are best obtained on a mine-specific basis.

Jan 1, 1987

By S. R. Rannels, D. E. Rannels

"I. IntroductionThe alveolar surface of the lung is covered by two populations of pneumocytes, type I and type II epithelium. The type I cell, which accounts for most of the alveolar surface area and provides a highly specialized barrier for gas exchange (Rannels et al., 1991), is poorly understood. Although approaches to type I cell purification have been discussed, they have not been applied widely because of the lack of phenotypic markers to monitor isolation procedures (Dobbs et al., 1988; Danto et al., 1992). In contrast, the type II cell has been studied extensively, largely because of the development of reliable procedures for its isolation and primary culture. Investigations based on the use of purified populations of cultured type II cells have provided convincing evidence to support a role for the pneumocytes both in the maintenance of normal lung function and in the response of the lung to injury (for review, see Rannels and Rannels, 1989).While type II cells can be isolated by a variety of approaches, the protocols used most commonly are modifications of the gradient method of Dobbs and Mason (1979) or of the panning method of Dobbs et al. (1986). Purification of the cells based on density gradient centrifugation is reliable and consistent, with yields of 30 to 40 X 106 type II cells per rat of 230 g body weight. Isolation procedures applied to a minimum of three to four rats provide the best results, as lower cell yields are common with the use of fewer animals. The protocol below is designed to obtain a maximal cell yield from the lungs of six rats.II. Materials and InstrumentationMaterialsCalbiochem: DNase I (Cat. No. 260912); Corning: culture flask, 75 cm2 #25115; Costar: culture plate, 24-well #3424; disposable serological pipette #4101; Elastin Products Inc: elastase #E-134; Falcon: cellulose nitrate membrane filter, 0.22 µm, #7105; conical tube, 50 ml, #2070; culture dish, 100 mm, #3003; culture plate, sixwell, #3046; Fisher: BaS04 , #B68-500; NaCl, #5271-3; NaHC03 , #5233-50; Fort Dodge Laboratories: pentobarbital, #1206-lE; Gibco: Dulbecco's minimal essential medium (DMEM), #430-1600EC; Hanks' balanced salt solution (HBSS), #310- 4185AG; Joklik's modified Eagle's medium (JMEM), #410-2300EC; HyClone Laboratories Inc: fetal calf serum (FCS ), # A-1115-L; I CN Biochemicals (Flow Labora tories): amphotericin B, #16-723-48; newborn calf serum (NCS), #29-121-54; try pan blue, # 19 5 5 32; Na/gene: Erlenmeyer flask, # 100-4116C; Pharmacia: Percoll, #17-0891-01; density marker beads, #17-0549-01; Sigma: gentam1cm sulfate, #G3632; penicillin/streptomycin, #P3539; trypsin inhibitor, #T9128; Tetko: HC- 160 nylon mesh, #3-160-53."

Dec 1, 1995

By R. D. Berkenkotter

Titanium and iron assays obtained from cores of three diamond-drill holes from the Cebolla Creek titaniferous iron deposit were evaluated by statistical techniques to obtain information concerning the mineral characteristics of the deposit and to make a preliminary determination of sampling requirements for the deposit. A range of sample volumes representing sizes from one-sixth NX core 2 feet in length through full NX core 10 feet in length were prepared by split-ting the NX core with a diamond saw and combining pulverized splits. Results indicate the existence of at least two statistical populations having different average grades of iron and titanium. Each has an assay frequency distribution that is not normal but is highly peaked (leptokurtic). Frequency distributions of assays from specific altered zones of the drill holes appear to be normally distributed. Increasing the cross-sectional area of the sample unit to change assay volume did not result in significant changes either in assay values or the resulting frequency distributions of assays. However, when assay volume is increased by increasing sample interval, the shape of the assay frequency distribution changes, and a normal distribution of assays is approached. Positive correlation exists between titanium and iron assays. The degree of correlation, although very significant, is too low to use for prediction purposes. Although the amount of data from three widely separated drill holes is not sufficient to establish an average grade for this large deposit, it indicates a range of expected assay values and provides some information for determining requirements of future sampling for evaluation purposes.

Jan 1, 1963

By Gary A. Kingston

Rolled steel, steel forgings, and steel castings in the Pacific Northwest (Washington and Oregon) are produced principally in the Seattle, Wash., and Portland, Oreg., metropolitan areas. Steel-mill products are rolled from carbon and some alloy &eels by three companies into shapes such as reinforcing bar, rods, rounds, squares, flats, and hot-rolled strips; structural shapes, - such as angles, channels, and I-beams, also are rolled. Carbon and alloy steel ingots are poured and forged at a Seattle plant into ship shafting, drive shafts, billets, slabs, bars, rings, hooks, and other items. Static, shell, investment, and centrifugal castings are produced at 19 steel foundries in a wide range of steel specifications. All Pacific Northwest steel output is based on remelting steel scrap. Local iron ore might be used in the future to supplement steel scrap as a metal source. Ore reduction would probably be achieved by methods other than the blast furnace. Current melt-shop practice and problems are basically the same in Pacific Northwest steel plants as in cold-melt shops in other parts of the country. Quality steel production is receiving more emphasis in this region with the installation of modern analytical equipment and vacuum pouring and melting facilities.

Jan 1, 1962

By Raymond M. Stateham

Calculations based on data obtained from measurements of smoke from coal-fired powerplants predict that infrared imagers will be useful tools for smoke vision. Infrared imagers operating in the 3-to 5-um spectral region have been evaluated for this purpose. A mine opening 110 meters long was filled with smoke from burning coal, and two men, wearing breathing apparatuses, moved through the smoke to serve as targets. The men were detected and identified at 80 meters.

Jan 1, 1976

By M. R. Geer

Three coals from the Wilkes on - Carbonado district of Pierce County , Washington , were subjected to washability analyses to estimate the amount and quality of washed coal obtainable . Because the coals were unusually difficult to clean , the washability examinations were supplemented by table tests , tests in dense - medium cleaning units , and flotation tests . None of the coals could be reduced to the desired 10 percent ash by tabling and the response to flotation by two of them was poor . Dense -medium treatment provided coal of the desired quality , but with the most difficult coal the recovery efficiency was lower than usual .

Jan 1, 1964

By A. B. Hooker, L. C. IlsLey

The greatest hazard of early mining was from explosions of methane ignited by open lights . With the advent of safety lamps and forced ventilation this hazard was greatly reduced until the application of electricity to modern mining not only multiplied the sources of gas ignition but the accompanying , machines and haulage systems increased the amount of explosive dust , through which a methane explosion is more liable to become a major mine disaster , and thus greatly furthered the need of adequate ventilation to keep down the concentrations of methane . Adequate ventilation is still the best preventive of such explosions . However , even with a well laid out and controlled ventilating system the amount of air passing through entries and rooms is liable to vary within wide limits because of open doors , falls of rock , or other accidental causes . The percentages of methane under normal conditions should therefore be kept so small that they will not be increased to explosive proportions by short interruptions in ventilation . Mine ventilation and methane detection are inseparable safety precautions . The increasing importance of ventilation necessitates more accurato determinations of the methane concentrations throughout the mines . This paper discusses in detail some of the steps in the development of methane detection and specially notes the more accurate detectors now available . One of the earliest means of detecting methane was by a candle . About 1835 , John Buddle , Sr. , a noted mining man of his period , when questioned by a Parliamentary Committee as to the safety of using candles , replied :

Jun 1, 1933

By J. Sammarco

The U.S. National Institute for Occupational Safety and Health (NIOSH) is conducting mine illumination research to determine if light-emitting diode (LED) cap lamps can improve safety by reducing glare. Glare can impede a miner?s ability to see hazards and to safely perform their work. Another objective is to determine if a person?s age is a factor. This is important because the workforce is aging ? the average miner is now about 43 years old. Three cap lamps were used to evaluate glare: an incandescent cap lamp, a commercially available LED cap lamp and a NIOSH prototype LED cap lamp. Thirty NIOSH personnel from the Pittsburgh Research Laboratory (PRL) served as test subjects. Three age groups were established with ten subjects in each group. Testing was conducted in the Mine Illumination Laboratory (MIL) of NIOSH PRL. The results indicate no statistically significant difference in discomfort glare among the incandescent and LED cap lamps. However, an analysis of variance for disability glare indicates that the LED cap lamps were superior for the older subjects. Disability glare scores for the oldest subject group improved 53.8% when using the NIOSH prototype LED cap lamp compared to the incandescent cap lamp and 36.5% compared to the commercial LED cap lamp. It ap­pears that, given the conditions of this study, LED cap lamps will not increase discomfort glare and can enable significant improvements in disability glare for older workers. It is also evident that not all LEDs are created equal. The disability glare improved the best for older workers when they used the NIOSH prototype LED cap lamp, which has a different spectral power distribution (SPD) (more short wavelength energy) than the commercial LED cap lamp. Therefore, for disability glare, the results suggest that the SPD is an important factor to consider in cap lamp design.

Jan 1, 2009

By W. Hodge Caraway

This report presents the results of an evaluation of several indirect methods of measuring the water content of oil-reservoir rocks. The water content of oil-base cores is considered to be most nearly representative of the water content of the undisturbed petroleum reservoir and therefore, the direct method of measuring the volumes of water in cores cut in oil-base drilling fluid was adopted as a standard for comparison. The indirect methods evaluated included (1) displacement through a semipermeable membrane by air, (2) centrifuge, (3) evaporation, (4) mercury injection, (5) chloride dilution and (6) electric logs. Approximately 270 samples of cores from petroleum-reservoir rocks were used in the study. The cores, most of which were cut with oil-base mud in the hole, were taken from oilfields in California, Texas Gulf coast, Colorado, Oklahoma, and Alaska.

Jan 1, 1959

By Raymond B. Ladoo

The uses for which ground talcs are suited closely depend upon their physical and chemical properties , but , in spite of this fact , little scientific investigation has been made in order to devise quick and accurate tests for the determination of these properties . The chemical properties of talc are inherent and may not be altered or modified except by selective mining or by chemical processes not practical in the present status of the industry . However , the determination of chemical properties is not so important , for most uses , as of physical properties , although sometimes certain chemical characteristics are perhaps unduly insisted upon by chemists in some industries . Physical properties are dependent both upon mineralogical characteristics and upon methods of grinding and sizing and may thus be partly changed or modified by changes in practice . There is so little known of the chemistry and physics of the various processes in which talc is used that the purchase and sale of talc is governed more by rule- of- thumb methods dependent upon individual opinion and often , prejudice , than by accurate , standard tests . This not only causes unwarranted price fluctuations , but injures both the producing and consuming industries by creating false ideas of the suitability of talc for various uses . It thus seems important that present tests be standardized and made uniform for the whole industry , and that new tests devised to fill the existing gaps .

Jul 1, 1920

By V. Ferrari

This report documents the three-phase program to design, fabricate, test, and demonstrate economical and practical methods of reducing noise levels on underground coal mining portal buses (mantrip vehicles). The noise-control treatments applied to a production-model portal bus were as follows: ? Wheel/rail vibrations were isolated from the vehicle frame by inserting elastomeric materials between suspension components. ? Vibration-induced noise was reduced by replacing all large sheet metal panels (except floor plates) with damped steel panels. ? Motor noise was reduced by tight-fitting covers made from damped steel and lined with sound-absorbing material, and by elastomeric motor mounts. ? The standard spur gears used in the traction drive system were replaced with helical gearsets. The program achieved the goal of reducing the average sound-level to below 85 dBA for typical operating conditions.

Jan 1, 1981