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By J. W. Snavely

WITH all the advantages of handling bulk materials by means of belt conveyor also go some problems, one of the most persistent being that of cleaning. When sticky materials are being carried; the build-up of material on the return idler rolls results in difficulty of belt training. Much attention has been given to the problem of cleaning conveyor belts, and a great variety of cleaning devices have been developed. Even the best involve troublesome maintenance, and none can completely remove the fine particles imbedded in the belt cover, which cause rapid wear of the return idler rolls, and at the same time, of the belt cover as well.

Jan 12, 1951

By M. C. Fuerstenau

Collophane, cryptocrystalline fluorapatite, is examined as a substrate for plant water and wastewater remediation. The attenuation of Fe3+, Cr3+, Fe2+, Cd2+, Hg2+ and Pb2+ is presented as a function of metal ion concentration, amount of collophane, initial pH and conditioning time. TCLP results for Pb2+ contaminated collophane are presented. Mechanisms of adsorption for divalent and trivalent species are suggested. Key words: Collophane, Wastewater remediation, Heavy metal removal

Jan 1, 2003

By A. P. Grossman

'This report was prepared by Shell Oil Company, Mining Ventures Department in accordance with Cooperative Agreement No. 14-09-0070-b53 dated September 10, 1976, between the United States of America, Department of the Interior, Bureau of Mines and C(b) Shale Oil I Project, Ashland Oil Inc., Shell Oil Company, Operator. After completion of this report the Shell Oil Company withdrew from participation In the C(b) Shale Oil Project and advised the Bureau of Minus that plans for publication of this report had also been withdrawn. The Bureau of Mines acting under terms of the Cooperative Agreement hereby releases this report for general information.

Jan 1, 1976

IT is not necessary to enter into a long discussion of ordinary bells, because every master carpenter or blacksmith knows how to make those levers with a crossbar that are called storks. This is nothing other than a board that has a thick and heavy head and looks more like a dolphin than a bird. This has a long tail in the form of a handle so that it makes a more powerful lever. As can be seen in every bell tower and other place where there are bells, it has, crosswise above the point where the cannon of the bell is fitted and fastened in, an iron bar which is arched and which has its two ends turned horizontally. These are made round so that they may turn easily when they are held by two steel rings or in two metal grooves or on glass pillows. In this, the more the transverse rod is arched,

Jan 1, 1942

By F. A. Rutledge

The Rainy Creek deposits lie at the western base of the Kilbuck Mountains, about So miles southeast of Bethel, in southwestern Alaska. The deposits were brought to the attention of the Bureau of Mines by placer miners on Rainy Creek after cinnabar concentrates were recovered by their gold-mining operations. In August 1947 the Bureau excavated 1,500 feet of dozer trenches totaling 2,547 cubic yards. Further hand trenching in the bottoms of the dozer trenches on the surface totaled 1,440 linear feet, or 40 cubic yards. Nineteen samples were taken for analyses.

Jan 1, 1948

By Kun Wang, Xinhui Li, Huaqing Xie, Qingbo Yu, Qin Qin

"Three typical model compounds of bio-oil (ethanol, acetone and phenol) were studied in the steam reforming process for hydrogen production. In the thermodynamic analysis, the three componds showed the similar trends. The hydrogen yields increased with the increase of steam/carbon (S/C) ratios, and the temperatures of the maximum hydrogen yields moved afterward to low temperature zone. However, the hydrogen contents were just about 70%. For improving hydrogen yield, a new system for steam reforming of bio-oil with site CO2 capture was put forward. This system required the catalst with the larger granularity having greater mechanical strength and higher abrasion resistance. So, six Ni-base catalysts loaded on Al2O3 particles prepared were used and among them, Mg-Ni/Co catalyst showed the best catalytic performance. For the simulated bio-oil (the mixture of the compounds), the hydrogen yield can attain 63% with Mg-Ni/Co catalyst with the good stability and regeneration ability.IntroductionCurrently the interest in the use of hydrogen as a clean energy carrier is increasing, and the main way for producing hydrogen is steam reforming of fossil fuels, containing steam reforming of nature gas, naphtha and coal. But this way caused substantial amounts of CO2 emitted, and these sources of hydrogen which are non-renewable energy will eventually be used up [1, 2]. As a kind of renewable energy, biomass is recognized as an attractive alternative to fossil fuels, because of its neutral CO2 emissions [3]. There are mainly two thermochemical processes using biomass to produce hydrogen, gasification and flash pyrolysis followed by steam reforming (SR) of the biooil produced in the flash pryolysis process [4]. The latter was known as one of the most promising and economically viable methods for hydrogen production [5]. In the last decades, the biomass flash pyrolysis technology was adequately developed and fairly mature [6]. But the steam reforming of bio-oil is still at the research stage and yet has been leading to more and more concerns by the researchers. In their research, the catalysts were widely studied and yet mainly were powdery[7-10], and the reactors manily were fixed bed reactors[11-13], readly causing the carbon deposition and the catalyst deactivation, against the continuous running. In this paper, a new systerm was put forward and could realize continuous production of hydrogen, yet needed catalysts with the larger granularity having greater mechanical strength and higher abrasion resistance, as well as powdery CO2 sorbents which mainly calcium oxide based ones.In this paper, the thermodynamic analysis of the steam reforming processes of three typical bio-oil model compounds (ethanol, acetone, phenol) was performed, and the effect of S/C ratio and temperature on the hydrogen yield and the compositions of gaseous products were investigated. Then, a new systerm for steam reforming of bio-oil with site CO2 capture was put forward, and the catalysts with a certain granularity were prepared and studied."

Jan 1, 2014

By Lynne Chastain

The Eastern Shoshone and Northern Arapaho tribes of the Wind River Indian Reservation, Wyoming are interested in developing their industrial mineral resources. The U.S. Bureau of Indian Affairs (BIA), Division of Energy and Mineral Resources (DEMR) is assisting the tribes in evaluating the potential of their industrial mineral prospects for development. Gypsum occurs on both sides of the Owl Creek Mountains in the basal portion of the Jurassic Gypsum Springs Formation. The gypsum resources that are being evaluated crop out along the northern flank of the Owl Creek Mountains in the Sweetwater basin, a small topographic sub-basin of the Big Horn Basin. From October 1998, to April 1999, DEMR personnel mapped, sampled, and drilled the southcentral butte within the Sweetwater basin. Samples were analyzed for free and combined water, and major mineral oxides to determine gypsum purity. Gypsum purity averaged 93.6 percent for surface samples and 95.1 percent for drill core samples. The basal portion of the Gypsum Springs Formation is comprised of several beds of gypsum up to 9 feet (2.7 m) thick separated by 0.5 to 2.0 foot (0.15 to 0.61 m) thick lenses of siltstone and limestone. Overall gypsum in the formation ranges from 35 to 90 feet (11 to 27 m) in thickness. A resource of approximately 7 million short tons (st) (6.4 million metric tons [mt]) has been identified.

Jan 1, 2001

By Y. Baskin

Solid-solubility relationships in the Pseudobinary systems UAS-UP, UAs-US. UAS-UC, aid UAs-UN were investigated. The first two systems exhibit complete mutual solubility, whereas the component compounds in the other two systenzs are immiscible. The above information, together with solid-solubility data joy six additional pseudobinary systems , were analyzed for compliance wilh the Hurrze-Rothery rules for rnetallic systems. The relative size difference of the component nonmetal atoms was found to be the dopainant jactor determining the extent of solid solubility between the NaC1-type uranium compounds. The anionic and covalent radii of the nonmetal atoms appear to be inadequate for these systems, but compuled radii based on rare earth compounds yield consistent results for the uranium compounds. THE actinide elements, like metallic elements of the transition and rare earth series, readily form binary compounds with nonmetallic elements of groups IV, V, and VI of the periodic table. Of particular importance are the NaC1-type equiatomic compounds with carbon, nitrogen, sulfur, phosphorus, and arsenic. The uranium members of this family of compounds have high melting points, are essentially stoichiometric, and exhibit various amounts of mutual solubility. Thus, they are of interest for investigating the factors governing the extent of solid solubility. Previous investigators have determined the solid-solubility limits in the pseudobinary systems between the compounds UC, UN, US, and UP. Anselin et a1 .' reported complete miscibility in the system UC-UN. Baskin and shalek 2 and Allbutt et a1.3 reported that UP and US exhibit complete mutual solubility. Shalek and white4 reported partial miscibility in the system US-UC. At 1800°C the maximum solubility of UC in US is 40 mol pct, but that of US in UC is 4 rnol pct. shalek5 found limited solubility in the system US-UN; the maximum solubility of UN in US is 11 rnol pct at 1800°C, while that of US in UN is only 0.3 mol pct. White and askin 6 found very limited miscibility in the system UP-UC at 1800°C. Approximately 7 mol pct UC is soluble in UP, but there is no solubility of UP in the monocarbide. Phase relations in the pseudo-binary system UN-UP were investigated by askin.' Approximately 0.7 mol pct UN is soluble in UP at 1800°C, while UP is immiscible in UN. The present study was carried out to explore the extent of terminal solubility in the systems UAs-UC, UAs-UN, UAs-US, and UAs-UP. This information, combined with existing data, provided a sufficient basis on which to determine the factors governing solid solubility in pseudobinary systems containing NaC1-type uranium conpounds. I) EXPERIMENTAL 1) Materials. The compounds UC and UN were obtained from the Kerr-McGee Corp. and United Nuclear Co., respectively. The US, UP, and UAs were synthesized by reacting finely divided uranium with H2 S, pH3, or AsH3 gas at low temperature (300° to 500°C), followed by homogenization in a vacuum at moderately high temperatures (1400° to 1700°c).8-10 The materials were essentially stoichiometric, with the exception of UC, which exhibited a C/U ratio of 1.05. Oxygen was the major contaminant in these compounds, ranging from 0.05 wt pct in US to 0.30 wt pct in UC, and it was generally combined with uranium to form UO2. The UO2 content in these materials was usually of the order of 1 wt pct, and did not exceed 2 wt pct. Furthermore, no evidence was found for a high-temperature reaction between uranium dioxide and any of the compounds. Chemical analyses of equilibrated compositions in the systems UAs-UP and UAs-US showed that the non-metal atom to uranium ratios averaged about 1.01, and that the oxygen contents ranged from 0.06 to 0.22 pct. However, the small deviations from stoichiome-try or the presence of minor oxygen impurities do not invalidate the conclusions to be drawn from this study. 2) Experimental Procedures. The component compounds in powdered from were blended in the desired proportions for 5 hr in the ball mill that consisted of stainless-steel balls in a plastic container. Chemical analyses indicated very little metallic pickup from the blending operation and virtually no increase in oxygen content. The pellets were pressed in a 0.270-in.-diam steel die under 40,000 psi pressure. One wt pct of stearic acid dissolved in CCl 4 served both as a binder and as a die lubricant. Chemical analyses revealed that the stearic acid left no carbon residue in the sintered samples. The pellets were sintered in vacuum in an unsealed tantalum crucible. The temperature, measured with a calibrated optical pyrometer, was maintained at 1800" + 30°C for 3 hr. This was sufficient time for attaining equilibrium as no change occurred in either the lattice parameters or the sharpness of the X-ray patterns when samples were annealed for longer periods of time. The pellets were cooled with the furnace. Debye-Scherrer powder patterns were taken at room temperature with a 114.59-mm-diam Norelco powder camera and CuKor radiation (CuGI = 1.5405A). Unit cell dimensions were determined from a Nelson-Riley extrapolation to the high-angle reflections. The values for were precise to k 0.001A. 11) RESULTS X-ray and met allographic investigation revealed that complete mutual solid solubility exists in the pseudobinary systems UAs-UP and UAs-US. The lattice parameter vs composition plots, Fig. 1, show a

Jan 1, 1968

By Martin S. Oudenhoven

This report describes the results of a Bureau of Mines investigation in which the stress concentrations and distributions caused by inclusions in a strained elastic plate were determined, Finite element analyses were made for 168 models containing single inclusions of elliptical, ovaloidal, and rectangular shape. The variables studied included: horizontal-to-vertical loading ratios, (Sh/Sv) of 0,0.33,0.5, and 1.0; width-to-height ratios (w/h), of 0.25, 0.5, 2, and 4; and Young's modulus of inclusion to Young?s modulus of plate ratios (K ratios) of 0.33, 0.5, 2.0, and 5.0. The results show that the theory for elliptical inclusions can accurately predict the average stress along the x and y axes of symmetry for circular, ovaloidal, and rectangular inclusions from the width-to-height and K ratios. The actual inclusion shape was insignificant, suggesting that the average stresses in other inclusions of irregular shape (orebodies) can be estimated with the theory for an elliptical inclusion. An application of this technique to mining problems is presented. The stresses in the elliptical inclusions were uniform throughout the inclusion for all the models studied.

Jan 1, 1972

By D R. Peacor, J L. Mauk

Dioctahedral clay minerals in the volcanic-hosted Golden Cross epithermal Au deposit, New Zealand, have been investigated by petrography, X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy/analytical electron microscopy (TEM/AEM) to determine the nature of these minerals in a hydrothermal ore deposit. Heterogeneity in the distribution of dioctahedral clays is observed from the hand-specimen scale to the TEM scale, indicating that primary rock textures and fluid pathways (related to rock type, porosity/permeability and fluid/rock ratios), in addition to temperature, are important factors controlling the distribution. As the proportion of illite in mixed-layer illite/smectite (I/S) decreases, TEM observations show decreasing layer stacking order, parallelism of packets, and packet size, and increasing apparent porosity. AEM structural data show a corresponding decrease in AlIV, AlVI, and K+, and an increase in Si, Ca2+, and Fetotal. The observations of this study indicate that local dioctahedral clay mineral reaction progress is controlled mainly by permeability and structure, but that this is superimposed on a predictable, system-wide clay mineral distribution that is controlled by temperature and fluid/rock ratio.

Jan 1, 1999

By L. O. Howard

L. D. RICKETTS, New York, N. Y.-The advance which has been made in Smelting has been in the line of cheaper cost of handling, due to larger units and decrease in losses. At the International smelter, Mr. McGregor designed everything to handle the ore under cover. But we do find an unaccounted for loss of 0.7 per cent. of our copper, which is serious. Mr. Wallace has made a suggestion that I think metallurgists ought to know of and think about. He made it years ago-and that is that one of the chief losses is undoubtedly in the charging and discharging of the calcine cars. His idea is that possibly the dryers and heaters might be put immediately over the reverberatories So that they could discharge in conveyors. They could feed on both sides, and thereby the dust raised by discharging in the cars from the hoppers could be overcome. E. P. MATHEWSON, Anaconda, Mont.-I might Say a few words on the plants we have visited So far. I was particularly struck with the cleanliness of the plants, which is next to Godliness. I noticed also that the skull-cracker arrangement they have for handling their converter slag is very good. And they have paid considerable attention to ventilation, and are taking steps to take care of the health of the men. "Safety first" has been well looked after in all the plants we have visited so far. The steel structures are right up to date, and the buildings are of the most modern type, and everything is conveniently arranged. I think the designers of the plants in the Southwest are to be congratulated on what they have done.

Jan 12, 1916

Trans No. Place Date Vol. 1. Wilkes-Barre, Pa. May, '71 1 2. Bethlehem, Pa. Aug., '71 1 3. Troy, N. Nov., '71 1 4. Philadelphia, Pa. Feb., '72.. 1 5. New York, N. Y. May, '72 1 6. Pittsburgh, Pa. Oct., '72 1 7. Boston, Mass. Feb., '73 1 8. Philadelphia, Pa. May, '73 2 9. Easton, Pa. Oct., '73 2 10. New York N. Y. Feb., '74 2 11. St. Louis, Mo. May, '74 3 12. Hazleton, Pa. Oct., '74.. 3 13. New Haven, Conn. Feb., '75 3 14. Dover, N. J. May, '75 4 15. Cleveland, Ohio Oct., '75 4 16. Washington, D. C. Feb., '76 4 17. Philadelphia, Pa. June, '76 5 18. Philadelphia, Pa. Oct., '76 5

Jan 1, 1934

By R. H. Thompson

Preliminary safe distances for blasting wiring from typical electromagnetic sources are presented. The distances are for underground coal mines and electromagnetic sources in the frequency range below 10 MHz. The distances are based on measurements performed at 3 locations in each of 3 coal mines. The measurement apparatus, measurement procedure, measurement results and the rationale used in the calculation of the safe distances are all described. The safe distances presented are dependent on the measurement results and their interpretation. More measurements are clearly necessary to establish the validity of the suggested distances.

Jan 1, 1985

By Steve Chorley

Open-type, or main beam, tunnel boring machines (TBMs) can achieve impressive rates of production. This type of TBM typically outperforms other types of TBMs currently in use around the world. In good ground conditions, main beam machines have achieved production rates of more than 1 km/month (0.6 miles/month). However, installing effective ground support in poorer rock conditions on main beam machines can be a major cause of concern. The design of main beam machines is such that installation of ground support equipment, particularly at the front of the machine in what is commonly known as the L1 support zone, has traditionally been limited to rock drills and basic working platforms. Personnel working in the L1 zone have, until recently, been protected by roof supports and extended fingers, often with restricted access to working areas.

Jan 1, 2011

By A Turichshev

The synthetic rock mass (SRM) approach for modelling jointed and veined rock has been at the forefront of caving geomechanics research for years. A well-constructed and calibrated SRM model can capture the full rock behaviour at a macroscopic scale. Traditionally, SRM technology employed bonded particle models (BPM) due to their ability to model rock’s response to loading without prior specification of behaviour. The SRM modelling process requires the BPM to simulate intact rock and the subsequent introduction of fractures or veins by changing bonding characteristics between the particles. However, bonded particle materials have difficulty reproducing both the compressive and tensile strengths of intact rock. This and other limitations of BPM have been the driving force in exploring the potential of grain-based (2D) and bonded block (3D) models (BBM).This paper reports on recent work exploring the applicability of both BPMs and BBMs in 3D to the modelling of intact rock. The advantages and limitations of both BPMs and BBMs are addressed based on the results of numerical simulations using the PFC3D and 3DEC distinct element codes. The preliminary results suggest that BBMs are better suited for simulating intact rock behaviour than BPMs. Ongoing work aims to better qualify the applicability of BBMs under different conditions. This has significant implications for our understanding of rock mass behaviour in a caving environment.CITATION:Turichshev, A and Hadjigeorgiou, J, 2016. Simulating intact rock behaviour using bonded particle and bonded block models, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 453–460 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By John Nagy

A study was made in the Bureau of Mines experimental coal mine of factors affecting gas ignition by a cutoff explosive charge. Experiments showed that, although gas could be ignited under some circumstances, the probability under normal mining conditions would be low. The use of permissible explosives, relatively short-delay intervals in firing adjacent holes, blasting to a 6-inch kerf, and reasonable care in the placement of the holes favor safe blasting and are current practice in mining. The experiments also showed that the weight of the charge is not a primary factor in the ignition of gas by a cutoff charge. The quenching action of a first charge on the igniting action of a second was verified in a supplementary study. Related experiments have shown that gas at the face may be ignited by a single charge of explosive when fired with a light coal burden. Permissible explosives were less hazardous under these conditions than nonpermissible explosives. The frequency of gas ignition in cutoff and single-charge experiments increased as the linear distance between the sheared face and the opposing mine rib increased.

Jan 1, 1960

By James C. Ault, Walter W. Kaufman

This Bureau of Mines manual for design of surface mine haulage roads covers such aspects of haulage road design as road alignment (both vertical and horizontal), construction materials, cross slope, and drainage provisions. Traffic control and design of proper lane widths to promote safe vehicle movement are included, as are suggested criteria for road and vehicle maintenance and for runaway vehicle safety provisions. The aim of this publication is to provide those involved with surface mine haulage road design with a complete manual of recommended practices that, if implemented, will promote safer, more efficient haulage routes.

By Young D. R, Webb I. D

The hydro-chlorination of Fe2O3 and Fe304 has been investigated in the range 850-950¦C in order to elucidate the role of iron in the segregation process for nickeliferous laterites. The kinetics of Fe203 chlorination using 20% HC1 - 80% N2 gas mixtures is consistent with a single-stage structure control model, whereas Fe3O 4 exhibits a two-stage reaction mechanism. Oxygen potential measurements using a CSZ probe located above the bed and X-ray powder diffraction results confirm the proposed reaction scheme. When a serpentine nickeliferous laterite (1.03% Ni - 11.7% Fe) was chlorinated at 900¦C with a 20% HCl - 80% N2 gas mixture it was found that the iron oxide in the ore was extracted in a similar manner to the synthetic iron oxides. Also, it was found that the nickel extraction from the ore paralleled that of the iron and the tests indicated that for the major part of the extraction, the solid nickel species were in equilibrium with the gas phase. The recovery of nickel from laterite ores by the segregation process has been investigated by a number of workers and several extensive reviews of the literature associated with this field have been published (Iwasaki, 1972; Canterford, 1975; Wright, 1973).

Jan 1, 1987

By Howard B. Hamilton

Laboratory performance of mercury filled current limiting devices (CLD) used for high speed switching of DC circuits (600 volts and below, up to 1000 amperes) using a system involving a parallel connected vacuum switch with CLD and an additional series connected vacuum switch was verified in USBM Contract #HO 357079. This report details analytical work and field experimental tests to predict and control voltage surges associated with the high switching speed associated with the switching system. It also details tests conducted to demonstrate the fault current limiting ability of the CLD. Problems associated with designing a fault current limiting system are discussed.

Jan 1, 1978

By F. J. Plaul

The dominating technologies for steelmaking are the basic oxygen furnace (BOF or LD process, Linz-Donawitz) and the electric-arc furnace (EAF). The main iron input materials for both are liquid iron as hot metal, or solid iron as pig iron, DRI (direct reduced iron), HBI (hot briquetted iron) and scrap. Hot metal, pig iron (i.e., solidified hot metal) and DRI/HBI are virgin iron materials, which have to be produced from iron ore by so-called ironmaking technologies. The family of ironmaking technologies includes three process routes: blast furnace, smelting reduction and direct reduction. Driven by steadily increasing costs of raw materials in the last two decades, the sector has seen a number of new developments in ironmaking technologies, developments based on fluidized-bed technology. The main advantage of a fluidized-bed technology is that fine iron ore can be directly charged to the process without prior treatment; it does away with agglomeration and its concomitant cost, a step practised in blast-furnace, COREX® and MIDREX® processes. With Posco of South Korea, Siemens VAI Metals Technologies has successfully developed the FINEX® process, a smelting reduction based on the direct use of iron ore fines to produce hot metal. The key technology is the four-stage, bubbling fluidized-bed-reactor system, in which fine iron ore is reduced to DRI fines in a countercurrent flow with a reducing gas generated by coal gasification. Beside surveying the current state of the art, this paper discusses the technological principles of smelting-reduction and direct-reduction processes. The status of FINEX® and the outlook for further developments are described. Crucial to the successful development of the new ironmaking technologies for the direct use of fine ore was the scaling up of the fluidized-bed reactor system, which demonstrated new design features.

Jan 1, 2009