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By R. Barany

Thermodynamic calculations pertaining to the minerals gibbsite, kaolinite, halloysite, and dickite have been hampered by the lack of adequate heat and free energy of formation data. Previous data for gibbsite were highly uncertain, and there were no data for the other three substances. By use of hydrofluoric acid solution calorimetry, the Bureau of Mines derived heat of formation values from the elements and from the oxides for the four substances, and the data were combined with known entropy values to obtain the corresponding free energies of formation. The results show that gibbsite and halloysite are thermodynamically unstable with respect to the oxides (a- alumina, a- quartz, and liquid water) at 298.15° K,, while kaolinite and dickite are only moderately stable (to about the same degree), The instability of halloysite, in comparison with kaolinite and dickite, results in a 60°-lower equilibrium decomposition temperature.

Jan 1, 1961

By Jerry E. Olson

In 1984, the U.S. Bureau of Mines conducted a mineral survey of the Black Rock Desert Wilderness Study Area (WSA) (NV-020-620), which covers approximately 319,000 acres in Humboldt County, Nevada. About 90% of the WSA is underlain by Pleistocene desert playa sediments; the remainder is comprised of Jurassic-Triassic metamorphic rocks, a Cretaceous intrusive and Tertiary volcanic rocks. Most of the WSA is within a down-dropped fault block of the Basin and Range physiographic province. No mines or evidence of major exploration were identified within the WSA; but five claim blocks within or adjacent to the WSA and zones of anomalous character as defined by the Bureau of Land Management were examined. No mineral resources were identified, but anomalous gold, silver, and indicator element content of samples taken near Pinto Hot Springs indicate resources may exist. Lithium content of samples from near-surface sediments on the desert playa is too low for resources, out geologic conditions are favorable for higher concentrations at depth. Occurrences of zeolites are not considered to be of commercial interest. Approximately 27,000 acres are held under geothermal lease, and most of the WSA is of interest for oil and gas. No evaluation of these commodities was made by the Bureau of Mines

Jan 1, 1985

By John P. Coughlin

The Bureau of fines has tested a portable microseismic processor recorder at the Galena Mine, Wallace, ID, both in an environmentally controlled enclosure and, with minimal protection, in a working area of the mine. In both trials the device demonstrated effective and reliable data acquisition capabilities.

Jan 1, 1985

By Paul M. Tyler

This paper presents one of a series of digests of foreign mining legisla- tion and court decisions that is being prepared in advance of a general report relative to the rights of American citizens to explore for minerals and to own and operate mines in various foreign countries. This interpretation of the laws of Switzerland has been prepared from the best information available in ashington, but is released subject to correction and amplification, if necessary, by the proper American diplomatic and consuler officers, to whom it is being referred through the courtesy of the Department of State. Sitzerland is a small country in which little mining is done, yet it has a voluminous body of mining legislation. There are two salt-mining districts in Switzerland; that at Bez, Canton of Vaud, belongs to the Canton but the deposit is worked by a private company; and those at Schweizerhalle, Rheinfelden and Ryburg are worked by a joint stock company formed by the Cantons interested. Iron ore is mined at Gonzen, Canton of St. Gallen, and large beds of gypsum are worked, mainly for domestic consumption. In general, however, although many kinds of minerals are said to have been found in Switzerland, mining operations are irreguler end relatively unimportant. Even during the world war only about 2,500 persons were employed in mining establishments and most of these were in under round stone quarries. On the other hand, the republic comprises 22 Cantons, of which 3 are divided, making 25 units, and in the absence of generel Federal legislation, each of these units virtually has its own distinct mining la Under these circumstances, it is obviously inadvisable to review the mining lars of Switzerland in the same detail as those of other countries which Lave been digested in this series. For the lars of individual Cantons, as well as for a more comprehensive summary of the Swiss legislation as a whole, the reader is referred to a recent German publication." Many of the statements in the present paper can be traced to this source. Acknowledgment is also made of the brief analysis published by anot..er German authority..

Jan 1, 1933

By E. J. Gleim

This report describes a trip to Europe in the interest of safety in coal mines. It reviews the Eighth International Conference of Directors of Safety in Mines Re-search, which met in Dortmund-Derne, Germany, July 5-10, 1954, to discuss results of studies made in different countries to improve health and safety conditions under-ground. It also summarizes information on subjects of special interest in the United States gained by the writer in visits to mining experiment stations in Belgium, France, and England. The efforts being made to protect life and property underground were discussed, and ideas and experiences were interchanged freely, not only during the conference but also during visits to the several countries. Helpful information was obtained on many topics of interest, but time did not permit as thorough a discussion on some of them as might be desired.

Jan 1, 1956

By R. P. Maloney

The Bureau of Mines conducted a reconnaissance of the less accessible parts of the Beluga River coalfield in August 1957 to determine, if possible, which areas were most favorable for developing large reserves of coal suitable for open-pit mining. Several outcrops of subbituminous coal were observed within an area about 30 miles long and 3 miles wide; neither the length nor the width of the coal-bearing area was delineated by the examination. Coal beds 30 feet thick or more outcrop at two places, and beds 5 to 20 feet thick or more outcrop fairly abundantly along the Beluga River and its tributaries The coal measures appear to occur in a series of folds. The overburden comprises glacial gravels and poorly cemented sandstones and ranges from 20 to 400 feet in depth. Few partings were seen in any of the coal beds. Samples ranged in calorific value from 6,240 to 8,246 B. t. u. on an as-received basis. Adequate water is available for stripping by hydraulic methods.

Jan 1, 1958

By F. S. Crawford

This study was made to find methods of preventing back strains, among workers in brick plants, however, the information should apply to other industries that employ hand labor too process materials. The report is based on information in letters from. Bureau of Mines engineers and other safety men in the United States who visited numerous brick plants. Back strains, as wall as hernias and other muscular strains, result when certain body structures are subjected to strains greater than, they can withstand. Such breakdowns may be prevented simply by not straining these body structures. This is simple in theory but complicated in practice. It requires primary education of new workers and reeducation of older workers in the best method of lifting, preemployment physical. examinations to select employees for the jobs that require constant lifting, all possible mechanization of material-handling operations, relocation of machinery, and elevation of working surfaces to reduce to a minimum the muscular effort the workers must exert to perform operations impossible to mechanize. Accidents of any kind are a total bee for the American economy and decrease productivity; whereas mechanization raises the level of productivity and constitutes progress toward total safety. Heavy lifting should be done mechanically whenever possible, saving the men to direct the machines. This is an essential step in preventing strain accidents.

Jan 1, 1953

By E. G. Davis, H. P. LeVan, L. S. Smith

Leaching of a Georgia umber ore when using both ferrous sulfate and pickle liquor was studied in the laboratory . The ferrous sulfate content of the leach solution was the major factor affecting the extraction of manganese from the ore . Time , temperature , and the sulfuric acid content of the leach solutions had relatively little effect on leaching of manganese from the ore ; however , these factors did affect the amount of iron extracted from the umber and/or precipitated from solution . Simulated countercurrent leaching of the ore with pickle liquor containing 130 gpl (grams per liter ) ferrous sulfate ( 48 gpl ferrous iron ) produced a pregnant solution having 16 gpl manganese and 41 gpl iron . Filtration tests of the leach slurries indicated that separating the leach solution and solids by vacuum filtration was impractical , whereas pressure filtration was feasible when the cake thickness was limited to about three- fourths of an inch . Fired pellets of the filter cake yielded a firm , hard product analyzing 56 percent iron and less than 0.1 percent sulfur .

Jan 1, 1964

By H. William Zeller

The Bureau of Mines performed laboratory research into the effects of a barium-based fuel additive (the "postflame" type) on diesel particulate matter (DPM) emissions. The 5.6-L, six-cylinder test engine is typical of types certifiable for use in underground mines. Test parameters consisted of additive concentration and engine loads, speed, and air intake restriction. DPM emissions, including condensed volatiles, were measured gravimetrically. Also measured were gaseous emissions including carbon monoxide, nitrogen oxides, and hydrocarbons. The fuel additive was effective, reducing DPM up to 75 pct, when used at a concentration of 0.09 wt pct (one-fourth of the concentration recommended by the manufacturer). The additive was most effective at the highest fuel-air ratios, reducing DPM from 400 mg/m3 for untreated fuel to 120 mg/m3. At light loads, 25 pct of full rated, no DPM reductions were measured. Based on these results, the additive is recommended for use in diesel fuel, at a concentration of 0.09 wt pct, to power underground mining equipment as long as certain conditions are met: that a beneficial DPM reduction is verified, that the minimum required quantity of additive is used, and that potential adverse effects such as increased nitrogen oxides are checked.

Jan 1, 1990

By J. H. Stears

This Bureau of Mines report presents information on the use of steel supports in U.S. coal mines, including accident statistics for a 3-yr period and a survey of present applications and problems. It also contains a summary of available steel arch configurations and a description of steel support design criteria for ground control applications.

Jan 1, 1984

By John W. Frey

Although there are certain general uniform provisions in the laws ... of the several Provinces of Canada the differences are so great that it is considered advisable to present digests of separate mining laws rather than a digest of Canadian mining law as an entity . This analysis , accordingly , has been divided as follows : Nova Scotia , New Brunswick , Quebec , Ontario , British Columbia , and a group of Provinces under Dominion Law .

Sep 1, 1930

By J. B. Stephenson

The Bureau of Mines, under an interagency agreement with the Department of Energy (DOE), investigated the feasibility of hardfacing the critical surfaces of valves and similar devices by chemical vapor deposition. The purpose of this research was to increase the wear resistance of these components for use in the abrasive and erosive environment of coal gasification units. Tungsten and molybdenum coatings were produced on nickel-plated carbon steels and stain-less steels by hydrogen reduction of the metal hexafluoride at 325° to 600° C. Titanium nitride coatings were produced on low-carbon steels by the reaction of titanium tetrachloride, hydrogen, and nitrogen at 1,000° C. Titanium carbonitride coatings were produced on low-carbon steels by the reaction of nitrogen, hydrogen, and methane at 900° C. Tungsten, molybdenum and titanium nitride coatings were formed on 6-, 10-, and l2-inch (0.15-, 0.25-, and 0.30-meter) ball valve seats for evaluation in the low-Btu coal gasification pilot plant at the Morgantown Energy Research Center, Morgantown, W. Va.

Jan 1, 1979

By Edwin C. Reeder

This is one of a series of papers dealing with mining methods and costs prepared under the sponsorship of end in cooperation with the United States Bureau of Mines. The mining methods described in this paper are those used in one of the large mines producing fluorspar in the Kentucky-Illinois fluorspar field, located in southern Illinois and western Kentucky on the Ohio River. The occurrence of ore and the methods of wining are similar to those in other mines in the district; therefore information regarding methods and the results obtained should be of interest. Improvements in methods have been made as experience developed the need of them. The trine is situated at Rosiclare, Ill., on the Illinois Central Railroad, and shipments are also made b r barge on the Ohio River.

Jan 1, 1930

By F. E. Griffith, C. H. SEELING

Cardox blasting is used widely in coal mines in the United States . A model of a Cardox blasting device was approved by the Bureau of Mines subject to certain conditions and limitations , and the approval was extended to other models from time to time . Certain special hazards are entailed in the use of Cardox as with explosives . One of these is flying shells . In some blasts , the Cardox shell is violently ejected from the borehole and flies like a projectile , frequently ricocheting off solid objects and striking points considerably off the line of its initial flight . Flying shells have been known to pierce the webs of structural - steel beams , to pass through both sides of allsteel mine cars , to be driven through stout hardwood timbers , to knock out timber sets , to damage loading equipment , and to break or short - circuit power lines . A considerable number of shot - firers and other workers have been struck by flying shells and killed or injured . Accidents from this cause , although not as frequent as other types of mine accidents , are usually serious , closely approximating accidents caused by blasting with ordinary explosives . The increasing number of such accidents prompted a Bureau of Mines field investigation of possible methods of preventing dangerously violent ejections of Cardox devices . This report contains pertinent data collected during the investigation and describes methods tested and discarded as well as the development and proof of an apparently satisfactory method .

Jun 1, 1943

By Paul W. Jeran

Subsidence over a series of longwall panels undermining sloping terrain in southwestern Pennsylvania was monitored to verify the Bureau of Mines subsidence prediction model for the northern Appalachian coal region. Comparison of the field data to model output shows close agreement. Vertical movements over each panel ceased with the mining of the adjacent panel. Horizontal movements were significantly affected by topographic slope. The distribution of horizontal strains over each panel were similar, with a zone of compression occurring over the center of each panel. The zones of compression were flanked by zones of tension toward the rib. The magnitude of the tensions were affected by the slope. The strains developed at the completion of each panel were not significantly altered by the mining of subsequent panels.

Jan 1, 1988

By L. C. IlsLey

Minin,g Qr col-cu.ttint till:I chines are 1?;\i9ng the _m9t wideiy .used de1sses ()f mining equipment.· These 1T:.i:1Chines ,.--re practicaily t-tl\·operc1_ted eiyher_by compressed .iir or by electric. ·motors. According to &.ta• compiled _ from the 122. issue COAL CATALOG\JE. OJMEINED WITH; OOAL "FIELD 'pf!:fC'TOTl1, bf 7,088. mnes from which reports were obttiined there -are 3895 mines that u.se coal-cutting eql;lipmen:ts,, 'f'hi report lists 20,031: r.ct:lchines, 17,&75 being operated by·elct:i.c.m<;>_tors··:r;id :the remtiinder by compressed i.r motors,· ,-. · ', .. . · .. ··, .. _ ,· .,, .. .. . . . . . : ; "'l t:: On tl.Ccou-nt .. of the wide· use of coc:11-cutting -.:i"cliine_- any Stat!;ls have issued regulationa as "to their operation dnd be to safety precautions that.should be observed J especially in gaseous mines.

Oct 1, 1922

By J. D. Noll

The Mine Safety and Health Administration (MSHA) has promulgated rules to limit the exposure of metal/nonmetal underground miners to diesel particulate matter (DPM). These rules have resulted in many types of control tech­nologies being implemented including diesel particulate filters (DPF). The passive type DPF is the most desirable because it requires little maintenance and it regenerates while the vehicle is operating. One problem with passive DPFs is that many vehicles cannot develop the sustained exhaust temperatures needed to initiate DPF regeneration, and thus it is required that the DPF be catalyzed to decrease the temperature needed for regeneration. In some past studies, such catalyzed filters have been shown to cause an increase in the nitrogen dioxide concentrations in the exhaust, resulting in a potential health hazard. In this study, a lightly catalyzed DPF along with a fuel-born catalyst were employed to help reduce the DPM emissions from a 980F loader used for cleanup in a stone mine. After 30 days of use, the filter continued to regenerate successfully at the exhaust temperatures generated by this loader, substantially reduced DPM concentrations emitted in the exhaust, and did not cause a measurable increase in nitrogen dioxide levels that could be attributed to the device.

Jan 1, 2009

By R. C. Diehl

Coal, fly ash, and flue gas samples were analyzed for mercury (Hg) by double gold amalgamation-flameless atomic absorption spectrophotometry. The purpose of the study was to elucidate the fate of the trace mercury in the coal when the coal is burned. Samples were collected from a bench-scale 100-g/hr combustor, a 500-lb/hr combustor, and three coal-burning powerplants. In all cases mercury was found in the fly ash. The amounts ranged from about 9 to about 70 percent of the mercury in the coal that was burned.

Jan 1, 1972

By M. J. Ankeny, J. J. Forbes

The United States Bureau of Mines often receives inquiries from the mineral , petroleum , and allied industries concerning the essential steps to be taken in the formation of Holmes Safety chapters and councils . The purpose of this circular is to answer in a general way such inquiries and to relate briefly the history and work of the Holmes Safety Association to the present date .

Jul 1, 1931

By John E. Shelton

Flotation tests were conducted on two samples of copper-nickel-bearing ore from the Harriman area near Rockport, Maine. The samples were taken by Roland F. Beers, Inc., for tests in cooperation with the Federal Bureau of Mines. One sample, analyzing 0.38 percent copper and 0.71 percent nickel, was essentially a disseminated pyrrhotite in hypersthene. Pentlandite, chalcopyrite, pyrite, and millerite were intimately associated with the pyrrhotite. Locked series flotation tests on this sample showed that 87.4 and 73.4 percent of the copper and nickel, respectively, could be recovered in a bulk concentrate that analyzed 3.47 percent copper and 5.34 percent nickel. The copper-and nickel-bearing minerals were collected with sulfhydric collectors in an alkaline circuit. Cleaning the concentrate three times with the addition of pH regulators was sufficient to attain the previously stated grades. The second sample had analyses of 0.31 percent copper and 0.85 percent nickel; talc and hypersthene were the main gangue minerals. Bulk sulfide flotation, made while depressing the talc, resulted in a concentrate that analyzed 2.33 percent copper and 4.70 percent nickel at recoveries of 70.0 and 54.4 percent, respectively. Flotation of the talc followed by bulk sulfide flotation resulted in a nickel content greater than 5 percent. A locked-series test showed that 60.7 percent of the copper and 73.7 percent of the nickel could be recovered at grades of 1.29 and 4.85 percent, respectively.

Jan 1, 1961