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By Warren Hastings

This paper describes the methods and costs, in units of labor end materials, of sinking a 7 compartment vertical shaft 1,261 feet through a fractured, water-saturated formation. The shaft, designed for hoisting 2,500 tons a day, is at Friedensville, Lehigh County, Pa., approximately 6 miles south of Allentown and Bethlehem. It was sunk by the E. J. Longyear Co. under contract to the New Jersey Zinc Co. Preparation for shaft sinking W8A begun July 1, 1947, and sinking was completed August 18, 1952. A total of 604,858 man hours was required to sink the shaft.

Jan 1, 1954

By B. W. Gandrud

To say that the treatment and handling of the "fines" is the most difficult phase of coal preparation is probably an understatement of facts. It is the fine sizes from about 1/16-inch to 0 that are mainly responsible for the inescapable sludge and slurry problems at plants using wet methods of preparation. Sludge and slurry are a problem from the standpoints of both cleaning and dewatering. They cannot be cleaned satisfactorily by "gravity" methods, which are used so extensively on coarser Sizes, due to the fact that fine sizes, particularly from 65-mesh to 0, do not follow the same laws of settling as do the coarser sizes. Although fine sizes are cleaned more successfully on wet-wash tables than in jigs, even tables as usually operated in coal-preparation plants fail on sizes below 100-mesh. As to other phases of the, sludge and slurry problem, wet coal preparation plants are almost universally beset with troubles in connection with the recovery and dewatering of the fine sizes from about 14-or 20-mesh to 0. The sizes finer than 100-mesh further complicate the problems in a wet preparation plant by their tendency to stay in suspension and build up a troublesome load of solids in the circulating water. In order to prevent too much trouble from this source, it is, customary at most plants to bleed a fair-sized stream out of the circulating system continuously and replace it by addition of fresh make-up water. The slurry water withdrawn from the circuit is usually run to waste, in which case it carries with it a considerable amount of fine coal, thus increasing the "washer loss." Another evil results from wasted slurry water in that quite often it finds its way into creeks and larger streams, creating stream-pollution problems.

Jan 1, 1948

By Robert H. Mattes

The Lake Lynn Laboratory is a multipurpose mining research laboratory operated by the Bureau of Mines and located in Fairchance, Pa, It consists of both surface and underground facilities. The initial focus of the facility, scheduled for full operation in fall 1982, will be on the problems of fires and explosions in mines. The initial experimental explosion was fired on March 3, 1982. The intent of this document is to provide the reader with detailed information on the physical capabilities of the Lake Lynn Laboratory. Subsequent publications will focus on the capabilities of Lake Lynn as compared with those of other similar facilities worldwide, and a comparison of initial explosion test results realized at Lake Lynn and comparable results from the Bruceton Experimental Mines.

Jan 1, 1983

By Robert E. Wood

The temperature dependency of the low-density viscosity coefficients, ?°T, of helium and of nitrogen, 100° to 1,000° K, is correlated with empirical equations, and the temperature and composition dependencies of the low-density viscosity coefficients, ?°T, of helium-nitrogen mixtures are correlated with the Chapman-Enskog expressions by using the Lennard-Jones (6:12) potential function. The residual viscosity, ?T,P - ?°T (the difference between the viscosity of a compressed gas and the dilute gas at a given temperature), was found to be a function of the thermal pressure coefficient, (?P/?T)V, and two parameters, a and 1, which are characteristic of gas composition. The equation ?T, P = ?°T + a [(?P/?T)V]ß represented 1,340 higher pressure experimental viscosity values with a mean absolute deviation of 0.86 percent, and this equation was used to compute viscosities of the gaseous helium-nitrogen system for a range of temperatures and pressures including those encountered in Bureau of Mines helium purification processes and in a crude-helium conservation gas reservoir. Tabular viscosities for helium, nitrogen, and 13 helium-nitrogen mixtures are presented for 110 temperatures, 133° to 740' K, and 49 pressures in the range 1 to 240 atmospheres. The accuracy of the tabulated viscosities varies because correlation parameters were obtained from experimental data of unequal reliability. It is estimated that uncertainties in the computed viscosity values are ±5 percent for the region 325° to 740° K, ±2 percent for the region 183° to 325° K, and ±5 percent for temperatures below 183° K. The latter uncertainty may rise to y10 percent as critical conditions are approached.

Jan 1, 1970

By M. M. Fine

"Button" type ore from the Cason mine, Batesville, Ark., can be up-graded to plus-40-percent manganese by mineral-dressing procedures. A simple process including gravity concentration and. magnetic separation yielded more than 50-percent recovery of concentrates containing 38.1 to 40.6 percent manganese. These values in turn could be raised to 41.4 and 42.8 percent, respectively, upon sintering to conform to size specifications. The Bureau of Mines in the past has surveyed and tested many manganese ores and prospects in an endeavor to alleviate the shortage of manganese. The present period of emergency again emphasizes the strategic position of the metal, and manganese investigative work is being stressed to find new ore bodies and to apply newer beneficiation techniques to the known deposits.

Jan 1, 1953

By Larry G. Stolarczyk

An underground medium frequency radio communications system has been developed and demonstrated in both coal and metal/non metal mines. The principal advantage of the system are its low cost, ease of installation and the ability to provide radio communications to any vehicle or roving miner in the underground mine. The system provides high quality radio coverage in work areas and along manways with existing "wireplant" conductors. The conductors include AC power cable, telephone cable, metal water and high pressure air pipes, etc. The measured communications range from the base station to mobile transceiver exceeded 12,500 ft without the use of repeaters. A cost/benefit analysis shows that the initial cost of the equipment can be returned 2-6 times in the first year. The mine productivity increases by approx. 13 percent.

By H. W. Gillett, E. L. Mack

"This report describes the trend of developments in electric brass-furnace practice in the last two years, and supplements Bureau of Mines Bulletin 202, ""Electric Brass-Furnace Practice"", which was published in 1922. In that bulletin it -as pointed out that some of the lines on which electric brass-furnace progress would take place were clear, but others were less so.Developments in foreign countries.Foreign brass-melters have not yet adopted electric melting to an extent comparable to its use in the United States. It is doubtful Whether all foreign countries combined use 100 electric brass furnaces; of these about 35 are of American make (Ajax, Detroit, Baily) and are operating in Canada, Mexico, England, France, Japan, Sweden, Switzerland, Spain, Norway, Germany, Argentina and Czecho-Slovakia.`The Rennerfelt furnace finds some use in Sweden (1)c, notwithstanding its high metal loss on alloys high in zinc, Two German firms are reported(2) to be using the Rochling-Rodenhauser induction furnace on bronze, the average energy consumption being given as 400 kw.-h. per ton. No comment is made on any trouble from the ""pinch effect"", A firm in Switzerland is reported (3) to use three 600-lb., direct-arc furnaces of its own design to melt babbitt, antimonial lead, coinage silver, nickel, copper, and brass. The metal loss on yellow-brass turnings is high. Use Of a direct-arc furnace in England, with precautions aimed to prevent surface overheating, vas abandoned (4) in favor of an Ajax furnace."

Apr 1, 1924

By Jeffrey Y. Foley

In 1980, the Bureau of Mines investigated the northern Darby Mountains on the Seward Peninsula, AK, for radioactive mineral deposits. Uranium is concentrated in silicified shear zones in biotite quartz monzonite of the Darby pluton. The shear zones are best exposed in steep, narrow, avalanche gullies; they are characterized by radiometric anomalies and by uranium and thorium geochemical anomalies. Radiometric and geochemical anomalies are also found over altered biotite quartz monzonite where there are no visible shear zones. The radiometric and uranium anomalies are often spatially, but apparently not genetically, associated with alkaline mafic and felsic dikes. Similar geochemical and radiometric anomalies over discolored altered zones and geochemical anomalies in sediments downstream from the altered zones indicate that additional areas may also be favorable targets for uranium deposits. Analyses of panned, heavy mineral concentrates show no significant concentrations of uranium or thorium in resistant heavy minerals. This indicates that radioactive elements in the Darby pluton are concentrated in soluble, nonresistant minerals that may constitute a recoverable uranium resource.

Jan 1, 1986

By David Schlain

A small alumina reduction cell with a graphite crucible and boron nitride liner was developed by the Bureau of Mines as the initial phase of a study of the reactions which occur in the reduction of alumina by the Hall-Heroult process. Operating conditions in the cell such as temperature, time, current density, electrolyte composition, and electrode materials may be varied easily. Aluminum was produced in the cell at a current efficiency of about 75 percent and a cell voltage of 2.7 volts. Although the data are not wholly conclusive, the operation of the cell did not appear to be greatly affected by large changes in temperature, electrode spacing, current density, and alumina concentration in the electrolyte.

Jan 1, 1963

By N. S. Dalal, Xianglin Shi

"The mechanism of vanadium(V) V ) toxicity is still not fully understood in spite of extensive current effort (1-3). The presence of a vanadium(V) V ) -dependent NAD ( P )H oxidase in cell membranes suggests that at least one of the pathways involves oxidation of NAD(P)H (1-3). Considerable effort has therefore been devoted to finding the mechanism of NAD ( P ) H-oxidation by va¬nadium( V ) (1-19). Recently Liochev and Fridovich (4, 16) provided a critical review of vanadium( V) -stimulated NAD (P )H oxidation by plasma membranes. They out¬lined a mechanism in which vanadium(V) V )-stimulated oxidation of NAD ( P )H by biomembranes involves an O2 - initiated free radical chain reaction (4 ). While the above may be the major pathway for the vanadium-me¬diated NAD (P )H oxidation in membrane-related sys¬tems, some recent results suggest that in the presence of NADPH the flavoenzyme glutathione reductase can function as a vanadium(V) V ) reductase (18). Because of the significance of this result in relationship to the mech¬anism of vanadium( V) metabolism and the novelty of the metal-reductase behavior of a flavoenzyme, we have car¬ried out additional studies on one-electron reduction of vanadium( V) by two other, related flavoenzymes: lipoyl dehydrogenase and ferredoxin-NADPH oxidoreductase. These two enzymes were selected because they are known to catalyze a one-electron reduction of Cr ( VI ) (19-21 ), which is isoelectronic with vanadium( V ).The present study also reports on the generation of hydroxyl ( • OH) radicals in the vanadium( V) -flavoen-zyme redox system without exogenous H2O2. The • OH study was undertaken because • OH radicals are known to be generated in reactions of vanadium( IV) with H2O2 (17,18,22-27). For example, Piette and co-workers (17, 22) have studied effects of vanadium(IV) IV ) on lipid per-oxidation and NADPH oxidation and suggested that va-nadium( IV) -induced • OH radical formation may play an important role in vanadium( V) toxicity. Carmichael (25, 26) investigated the reaction between a RNA /VO 2' complex and H2O2 with a view to probe the possible re-lationship between vanadium( IV) -mediated • OH radical generation and DNA damage. He has suggested that in this reaction the • OH radical adds to the C (5) carbon of uracil, causing nucleotide damage, similar to what occurs in the nucleotide /Fe2+ / H2O2 reaction (28) and in y-irradiated aqueous solutions of nucleic acids (29 ). To our knowledge, however, there is as yet no report on ·OH radical generation in any reaction involving the reduction of vanadium ( V) by a well-characterized enzyme, without exogenous H20 2 • The present study provides evidence that ·OH radicals can form in a flavoenzyme-mediated reduction of vanadium( V) to vanadium( IV) and that this process involves also the reduction of molecular oxygen ( 0 2 ) to H20 2 • The H20 2 thus generated reacts with vanadium( IV) to produce ·OH radical, in analogy with the Fenton reaction ( Fe2 + + H20 2 - Fe3 + + OH- + ·OH)."

Mar 1, 1992

By George E. Fish

This report describes investigations conducted by the Bureau of Mines from 1957 through 1959 in the Roseland anorthosite-titanium belt of Nelson and Amherst Counties, Va., for the purpose of studying the titanium resources of the area. Three titanium deposits containing much saprolite ore derived from the decomposition of anorthosite and diorite were selected for detailed study Following a reconnaissance of the reported titanium occurrences in the belt. These three deposits occur in or are associated with anorthosite. Most of the occurrences are situated on or near the contact between the anorthosite and the gneissic country rock. The saprolite deposits are as much as 1.5 miles long, 1,000 feet wide, and 100 teat deep and contain significant reserves of titanium-bearing material estimated in excess of 20 million tons. Where it was penetrated by drilling, the unweathered rock beneath the saprolite contains nearly the same titanium values as the saprolite.

Jan 1, 1962

By D. C. Dahlin

The U.S. Bureau of Mines investigated the magnetic susceptibility of minerals as a function of mag-netic field strength to determine how it might affect the potential for high-field magnetic separation as an alternative to other separation technologies. Single-mineral concentrates were prepared from specimens from the same deposit to compare magnetic susceptibilities of minerals that occur together and from specimens from different deposits to compare magnetic susceptibilities of like minerals. A vibrating-sample magnetometer with a superconducting magnet capable of producing a magnetic field of 7.16 x 106 Aim (90 kOe) was used to measure the magnetic moment of the samples. The data were then converted to specific magnetic susceptibility data and plotted as a function of magnetic field strength. Cursory studies were also completed on the effects of iron content and oxidation roasts on magnetic susceptibility in high fields. The results showed that magnetic susceptibility is essentially constant in magnetic fields above those needed to saturate ferromagnetic constituents. Although magnetic susceptibility is influenced by iron content and by thermal treatment, the changes are not large enough to influence separations in fields above 1.59 x 106 Aim (20 kOe).

Jan 1, 2010

By E. R. Bauer

Noise-induced hearing loss (NIHL) continues to be a concern of the mining industry. A new noise standard (30 CFR, Part 62) is aimed at reducing NIHL in mining through engineering and administrative noise controls. However, the difficulty and expense of implementing engineering controls can make administrative controls an attractive alternative for reducing worker noise exposure. Over the last three years, the National Institute for Occupational Safety and Health (NIOSH) has conducted worker noise exposure surveys in underground and surface coal mines and in coal preparation plants. The surveys revealed numerous possible administrative controls and an approach to implementation and analysis. The surveys have shown that worker dosimetry, time-motion studies and equipment noise profiling are important aspects of effectively utilizing administrative controls. A description of the approach for selecting, implementing and evaluating administrative controls and a list of possible administrative controls are reported.

Jan 1, 2007

By D. S. Kingery

Efficient transportation is necessary to complement modern mechanized mining methods. The increasing trend toward high-capacity face loading equipment has demanded equally efficient haulage methods; this has been met by increasing mine-car sizes, using larger locomotives, and increasing haulage speeds, all requiring properly installed and maintained haulage roads specifically designed for this type of traffic. The recommendations and specifications included in this circular were made to point out salient factors important to the proper construction and maintenance of track haulage roads and to serve as recommended standards for track installation and maintenance. GLOSSARY OF TERMS USED Haulageway. - The track, walkway, trolley wire, feeder lines signal end telephone lines, signals, telephones, support, and drainage of the entry referred to. Subgrede. - The base upon which the ballast is laid.

Jan 1, 1954

By Jaan Kiusalaas

This report is a self-contained User Manual for a computer program called SPASID -- Subsidence Prediction and System Identification. The program has two primary functions: (i) Precalculation of ground movements due to underground mining operations using the influence function method; (ii) Computation of influence function and site parameters from measured displacements. SPASID is written in FORTRAN and consists of four modules: (i) Preprocessor Module that prepares and maintains surface and mine data bases; (ii) Subsidence Computation Module that predicts movements of the surface; (iii) System Identification Module which is used to calculate the optimal influence function parameters, and (iv) Postprocessor Module for generating graphic displays of subsidence data. The last module is somewhat machine dependent but has internal documentation to indicate potential changes. All of the modules may be run in either batch or interactive mode. The manual does not assume previous knowledge of the influence function method or programming competence.

Jan 1, 1983

By Oliver Bowles

A conviction is growing that depressions and other adverse conditions are not entirely unavoidable if a knowledge of past achievements and shortcomings is intelligently, applied in shaping the course of industry. Mineral producers have available a source of such knowledge concerning; their industry in the statistical records of the United States Bureau of Mines, and by scanning, this increasingly exact history can obtain information on which to found a more stable future. This paper contains a brief history, covering more than 50 years, of the activities of the nonmetallic mineral industries as a group, followed by short histories of each of the more important commodities in which are noted the circumstances that lave influenced their development.

Jan 1, 1933

By G. M. Kintz

It is estimated that 10,000 lives were lost and $285,000,000 worth of property was destroyed by fire in 1937. Of the 103 fatalities in tie petroleum industry in 1938, 36 resulted from fires and explosions.3/ Everyone can help to prevent the tremendous losses, both in life and property, caused annually by fires and explosions, Forest fires occur every year, in which the tremendously intense heat wave ahead of the flame turns beautiful green trees into blazing torches like so much gasoline, vapor, and jumps over the tops of trees to start fires behind the firs fighters; prairie-grass fires occur, and a farmer in the path of the fire must plow a furrow around his home and outbuildings before the flame reaches them; and frequently automobiles are burned up in filling stations. Persons who have witnessed such sights know better than to throw a lighted match, cigarette, cigar, or hot coal from a pipe out of an automobile or to discard a fire or flame of any type in the forest, in the country, or in the city.

Jan 1, 1941

By Victor Spironello

The Bureau of Mines is studying cupola ironmel technology with the objectives of conserving high-quality raw materials through substitution and productivity. In the research re-ported here, a ize was modified by a gas-fired melting and/or ing chamber into the stack above the level of the coke bed, for study as a prototype for a coal-fired melting chamber. The modified cupola, in which natural gas was used to partially replace foundry coke, was evaluated in several trial runs. Data were obtained on furnace performance, metal and slag chemistry, and scrubber waters as particulates. Results of the modified ion were compared to those of conventional cupola operation. Although this research was preliminary--since the ultimate goal is to use pulverized coal instead of yielded ample evidence that the melting rate of a cupola can be icantly increased with less than a increase in energy input. Other evidence suggests that melting of low-density scrap can be enhanced and that scrap containing undesirable and/or oxidizable elements can be appreciably upgraded. This work is continuing and will include the use of pulverized coal of low rank to assist in melting.

Jan 1, 1984

By James L. Elder

The Bureau of Mines and the Alabama. Power Co. jointly conducted a first experiment in underground gasification of coal at Gorgas, Ala., during the fall and winter of 1946-47. This preliminary experiment showed that it was not difficult to maintain combustion of coal underground, and that coal in place could be completely gasified. It was noted that the high temperature developed by the gasification of coal in place brought about changes in overlying strata that appeared to be favorable to the process. The high temperatures caused the roof rock to become plastic, to expand, and to settle down on the mine floor directly behind the reacting coke face. These results were promising enough to warrant further investigation of the process. It was believed that if this action could be controlled properly with roofs of similar composition, it would tend to force the gas-making fluids underground against the coal faces. Plans for the second experiment were based in part on this favor-able roof action, and the successful operation of the planned initial straightline passages depended on this fact. Gorgas was chosen as the site for the second experiment for the following reasons: A tract of coal land of sufficient size was available and isolated from the main body of coal; the roof rock was similar in composition to that encountered in the first experiment; and the overlying strata were thick enough to eliminate some of the operating difficulties that had been encountered, In addition, power, water, and machine-shop facilities as well as an adequate supply of labor were available in this area, and the friendly cooperation of the Alabama Power Co. further recommended this site for the planned experiment.

Jan 1, 1951

By Laurence A. Dahners

As part of the strategic minerals program, the Bureau of Mines conducted a diamond-drilling project on three barite properties in eastern Tennessee and western North Carolina during the summer and fall of 1944. These properties, the Moccasin Gap prospect and the Krebs property in Cocke County, Tenn., and the Sandy Bottom mine of the Stackhouse group in Madison County, N. C. (fig. 1), are known to have produced some barite. The Bureau of' Mines project was planned to prospect for extensions of the ore bodies. A total of 3,169 feet of diamond drilling was done in 15 holes on the three properties. Tabulations of sample analyses and drill-hole logs are presented in this report. Two other mines of interest in the area are the McCoy and the Williams in Cocke County, Tenn. The Williams adjoins the Krebs. No drilling was done by the bureau in either of these properties.

Jan 1, 1949