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By R. G. Knickerbocker, A. L. Fox, J. Koster, P. R. Perry

"During the past several years, alunite from the Marysvale (Utah) region has been the subject of investigation by the Electrometallurgical Section of the Bureau of Mines. The nature and occurrence of this mineral, with considerable data on the Utah deposits, together with a number of results of preliminary experiments, have been given in a previous report. 6/ The geology of the Marysvale region has been reviewed recently. 7/The present paper reports the results obtained by a method involving the sintering of alunite with boric acid and subsequent treatment of the sinter to produce alumina and potassium sulphate.The preliminary work just mentioned had given indications of the separation of sulphate salts high in potassium from fusions of alunite with borax glass.During the course of further work along those lines, fusions of boric acid and alunite were tried. No separation of salts was obtained, but it was observed that rather complete removal of so3 from the alunite occurred and that the sinter could be leached with water to give a solution contain¬ing most of the potash and a residue containing most of the alumina. The reaction that takes place can probably be written 8/:"

Mar 1, 1939

By Andrew B. Cecala

The U.S. Bureau of Mines has designed and evaluated total mill ventilation systems at two different mineral processing operations. Both systems have proven very effective at reducing respirable dust levels throughout the mill in a cost-effective manner. A 25,500-cfm system installed at a clay processing mill provided approximately 10 air changes per hour. This system reduced respirable dust concentrations by approximately 40 pct throughout the mill building. The second evaluation was performed at a silica sand operation. Tests were performed with 50,000 and 100,000 cfm of ventilation to the mill building, corresponding to 17 and 34 air changes per hour. Average mill-wide respirable dust reductions were 36 and 64 pct, respectively. Not only did these systems reduce respirable dust concentrations and increase visibility throughout the mills, they were also easy to install and required minimal maintenance. A total mill ventilation system provides a general purging of the mill air; the system should be viewed as a supplemental technique to assist other dust control systems in operation.

Jan 1, 2010

By H. H. Schrenk, L. B. Berger, W. P. Yant, F. A. Patty

"The use of small such as canaries and white mice, for detecting carbon monoxide depends primarily on the fact that the volume of respiration of these animals in proportion to their volume of blood is much higher than for man. Accordingly, when animals and men are simultaneously exposed to a given concentration of carbon monoxide the animals will absorb it more rapidly and attain serious poisoning in less time than men. Prom a practical viewpoint the use of the animals depends on the margin of time between observable symptoms in them and serious poisoning in man, during which man can return to fresh air or use respiratory protection. It should be remembered, however, that during the time the animal is incurring a detectable degree of poisoning, man is also absorbing some carbon monoxide, and the margin of time is not very wide. Experience with canaries has shown that an occasional specimen may have a tolerance above the average of the species and fail to exhibit symptoms before man incurs a very discomforting and possibly a serious degree of poisoning.It is also well known that physical activity increases the demand for oxygen by the body, and the respiratory exchange and circulation of the blood are increased to meet the demand. This sets up a vicious condition if carbon monoxide is present in the air because the rate of absorption of carbon monoxide is not only increased by the increase in respiration and circulation, but the absorption of carbon monoxide decreases the capacity of the blood for carrying oxygen at a time when the demand is high. These facts, together with the increase in respiration and circulation which attend excitement, underlie the caution to be calm and to walk slowly and to reduce physical exertion to a minimum when exposed to carbon monoxide. For these same reasons, when using animals for detecting carbon monoxide it is endeavored to keep them active, thereby tending to increase the response of the birds and widen the time between observable effects in the birds and effects in the man. As rule canaries are kept fairly active through fright at the unnatural surroundings and in their endeavor to remain on the perch of the cage when carried into the atmosphere to be examined. They also experience an excitement stage with oncoming carbon monoxide poisoning. Sometimes, however, especially if the air is cold, they tend to be inactive and quiet. Ordinary mice and white mice become inactive with use and also with oncoming poisoning. They huddle in the corner or the cage, and thereby not only reduce their sensitivity but make it difficult to observe signs of poisoning."

Oct 1, 1930

The objectives of this research were to examine and to laboratory performance of several brands of rigid urethane een brands, produced by 13 manufacturers, were examined. was performed in a laboratory under controlled conditions. document the foam. Eight-All testing Preliminary laboratory tests included flame spread evaluations, flame penetration, ignition temperatures, air permeability, and adhesion. Having established arbitrary cutoff values, the original 18 candidates were narrowed to 8. More specialized tests followed. The effects of water immersion and dry aging on flame spread performance and other physical properties were then examined. This Bureau of Mines report was written to provide information for those concerned with using rigid urethane foam as a sealant. Its intent is to describe the various laboratory evaluations performed and to delineate the performance of each candidate. This report neither promotes nor discourages the use of rigid urethane foams. It presents results that will enable those responsible for using or enforcing the use of rigid urethane foams in underground mines to make informed decisions.

Jan 1, 1985

By T. A. Henrie, J. D. Marchant, E. S. Shedd

Cerium metal was electrowon in a fluoride bath from cerous oxide and tapped from the cell during prolonged operation . Electrolyte constituents were CeF , BaF₂ , and LiF. Twenty- seven pounds of metal of 99.8 percent purity were produced at a rate of 3 pounds per hour and tapped from the cell . Principal impurities were molybdenum , aluminum , oxygen , and carbon . The operating parameters , such as electrode geometry , bath compositions , and oxide feed rate , were investigated . Anode reactions were found to be important factors in cell operation . Stable cerous oxide reacted more uniformly at the anode surface than ceric oxide . Electrowinning was conducted in crucible hearths consisting of both frozen electrolyte and molybdenum metal . Both materials proved satisfactory and did not react with the molten cerium . Stable cerous oxide was prepared by carbothermic reduction and used as a feed material . Cell design proved to be an important factor in continuous cell operation . Complementary to the investigations of electrowinning of cerium , the metal was purified by electrorefining in a chloride electrolyte .

Jan 1, 1964

By X. Shi, K. S. Kaspnak

"The generation of free radicals from reactions of nickel (Il)-thiol complexes with molecular oxygen and model lipid hydroperoxides was investigated by electron spin resonance (ESR) utilizing 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a spin trap. Incubation of nickel (II) [Ni(II)) with cysteine in an aerobic environment generated hydroxyl (·OH) radical, which then reacted with cysteine to generate a carbon-centered alkyl ( · R) radical. Radical generation was inhibited under a nitrogen atmosphere. Model lipid hydroperoxides, cumene hydroperoxide, and I-butyl hydroperoxide enhanced the yield of these radicals and also generated an alkoxyl (·OR) radical. Radical yield decreased by approximately half under a nitrogen atmosphere. Although histidine did not cause radical formation in the reaction between Ni(II) and cumene hydroperoxide under aerobic conditions, the addition of histidine to a mixture containing Ni(ll), cysteine, and cumene hydroperoxide under the same experimental conditions increased the yield of · R radical but lowered the yield of ·OR and ·OH radical adducts. It thus appears that histidine caused the ·OH attack to be more site-specific. Similar results were obtained utilizing 1-butyl hydroperoxide. Penicillamine or N-acetylcysteine yielded similar results except that under aerobic conditions, reaction between Ni(ll) and N-acetylcysteine without hydroperoxide did not generate a significant concentration of free radicals. Under the same experimental conditions, cystine did not generate any detectable free radicals, suggesting an important role of the -SH group in Ni(II)-mediated free radical generation. The results indicate that free radical generation from the reaction of Ni(Il)-thiol complexes and molecular oxygen, and/or lipid hydroperoxides, may play an important role in the mechanism(s) of Ni(II) toxicity and carcinogenesis. INTRODUCTIONWhile nickel is a well-recognized carcinogen [l, 2]. the underlying biochemical mechanisms remain unclear (3, 4). Recent studies suggest that these mechanisms may involve oxidative DNA damage through free radicals, especially the hydroxyl (•OH) radical [5-13]. The mechanisms of nickel carcinogenicity and toxicity may also involve lipid peroxidation [14-21]. Unlike ferrous ion [Fe(II)], the Ni(II) cation itself does not directly react with 02, H2O2, or lipid hydroperoxides to generate free radicals [12, 21]. However, it has been reported that Ni(II) complexes with certain synthetic oligopeptides, e.g., tetraglycine or glycylglycylhistidine, make Ni(II) reactive with 02. This reaction results in transitory formation of Ni(III) and degradation of the organic ligand via free radical reactions [22]. Such Ni(II)-peptide complexes are also capable of reacting with H2O2 to produce oxygen free radicals [11, 12]. Although the cellular environ¬ment may not contain these particular peptide ligands that are known to render Ni(II) redox active in vitro, it does contain a variety of oligopeptides that are capable of forming Ni(II) complexes at physiological pH, and thus may facilitate Ni(II) redox activity in vivo. These oligopeptides include glutathione (y-L glutamylycysteinylglycine), carnosine (homocarnosine (y aminobutyryl-L-histidine), and anserine ( B-alany1-3-methyl-L-histidine)."

Nov 1, 1995

By Paris V. Brough

This paper, which describes the practice of milling custom ore, in addition to that produced under company and lease operations in the Tom Reed mines, is one of a series 'being prepared by the Bureau of Mines. ACKNOWLEDGMENT Acknowledgment is made to W. B. Phelps, managing director, and Jack Zwinge, superintendent, far permission to publish, a-ad to G. E. Jarpe, the present mill superintendent, for his assistance in preparing the paper. LOCATION The mill is in Oatman, adjacent to the Benjamin Harrison shaft of the Tom Reed Gold Mines Co., in the foothills on the western slope of the Black Mountains, western Mohave County. The railroad shipping point is Kingman, Ariz., 25 miles northeast of Oatman. Paved highway U. S. 66 passes by the mill. The altitude is approximately 2,700 feet.

Jan 1, 1937

By Lloyd A. Morley

This annual report details progress under USBM Grant G0155003 during the project period of January 1, 1977 through December 31, 1977. The report contains four principal chapters covering accomplishments in the mine electrical safety research areas of continuous monitoring, battery and battery-charging safety, and computer modeling. Highlights of the work are summarized in the last report chapter.

Jan 1, 1978

By James A. Wasson

This Bureau of Mines report summarizes the application of pilot flooding in the evaluation of a potential waterflood project. Aspects of pilot flooding discussed include choice of pilot location, confined and unconfined waterfloods, operational precautions, and comparison of predicted with observed performance. Summaries of published methods of pilot flood data analysis for determination of full-scale waterflood feasibility are presented and their use illustrated for example pilot flood data.

Jan 1, 1974

By William H. Pomroy

Spontaneous combustion fires involving high-sulfide-content ores are a relatively infrequent yet serious safety hazard in mining. They are also the cause of lengthy mine shutdowns because they typically occur in areas of a mine where abundant fuel material is present but which are inaccessible for fire fighting. This Bureau of Mines report describes research to design, fabricate, and test in the laboratory and field a system that warns of spontaneous combustion fires in metal mines. Overall performance of the detection system was found to be satisfactory, in that the system was capable of reliably detecting low levels of combustion products believed to indicate the preflaming stage of spontaneous combustion in metal mines. Installation of similar systems in mines with a high risk of spontaneous combustion is recommended. Principal operating problems and recommended corrective actions are also discussed.

Jan 1, 1987

By Walter E. Lewis

This circular presents the method of making tests and apparent results of comparing performance of tungsten carbide insert bits and steel detachable bits by the Cleveland-Cliffs Iron Co. at the company's mines on the Marquette iron range of Michigan. The mines are at Ishpeming and Negaunee, Mich., and include the Cliffs Chaft, Mather "A", Cambria-Jackson, and Mather "B". There are four general characteristic types of high-grade iron ore on the Marquette range. B. H. Boyum2/ classifies the Cliffs Shaft as "hard-ore" and the Cambria-Jackson and Mather "A" as "soft-ore" types of deposit. Shaft sinking through Jasper, slate, and graywacke was in progress at this writing at the Mather "B", with completion at 3,100-foot depth in August 1949. The many different kinds of rock and ore at the mines of the Cleveland- Cliffs Iron Co. and the experimental work being carried on with carbide in- sert bits make it possible to compare, generally, the carbide insert and steel detachable bit. The type of "hard ore" at the Cliffs Shaft mine re- quired close study of the possible use of the insert tit, and their records are more complete than those of the "soft-ore" mines. History and development of tungsten carbide tips inserted in rock drill bits have been covered by R. W. Adamson, C. H. Vivian, R. C. Sullivan,5/ and others. Tungsten carbide insert rock bits have only recently been introduced to the domestic mining industry. Although unusual performance records are being reported at operations employing the insert bits, the general adaptability of the tool to all rock types and the advantages to be gained by using carbide insert tits remains to be demonstrated. Insert-bit performance is being observed at numerous mines and quarries throughout the United States The several mining operations at the Cleveland-Cliffs Iron Co. at Ishpeming, Mich., is one site where exhaustive comparative tests of insert and conventional steel detachable bits are currently in progress. Results to date are sufficiently impressive to be of general interest to the mining

Mar 1, 1950

By W. J. Fullerton

This paper is one of a series being prepared by the U. S. Bureau of Mines describing mining and milling methods and costs at cement-plant quarries throughout the United States, end deals directly with methods and costs at the quarry and mill of the North American Cement Corporation at Catskill, N. Y. The process of manufacturing cement is described only as far as the final grinding of the raw materials. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent local operating expenditures only and not total production costs. It is recognized that publication of total production costs may in many instances cause embarrassment to individual producers, as well as to the industry as a Whole. On the other hand, operating costs are essential to the technical discussion and study of methods employed. The attention of the reader is specifically called to this differentiation in order that no misunderstanding; of the scone of the cost tabulations may ensue.

Jan 1, 1931

By J. J. Jakosky, D. H. Zellers

"IntroductionThe Bureau of Mines has been conducting experiments in underground communication during a period of several years, and a brief summary of what has been done is as follows:During 1919-1920, investigations were conducted with the geophone. This instrument was used extensively during the World War for detecting enemy digging and mining operations, by means of the vibrations transmitted through the earth strata.A preliminary investigation using short wave-length (200 to 300 meters) radio equipment carried out jointly with engineers of the Westinghouse Electric & Mfg, Co. during 1922.The step was to investigate ground conduction signaling, (called T.P.S. in Signal Corps parlance)."

Nov 1, 1924

By Chas. F. Jackson

The annual reports of the supervising engineering of the nine sections comprising the Mining Division are assembled in the following pages and constitute the annual report of the division. In planning activities, the aim is to adapt them to changes in conditions, in the needs of the mining industries, and in the public interest; those current activities that contribute most to problems of present concern are emphasized, investigations of less immediate importance being recessed, if necessary.

Jan 1, 1940

By Chas. F. Jackson

The annual reports of the supervising engineers of the nine sections comprising the Mining Division are assembled in tie following pages and constitute the annual report of the division. In planning activities, the aim is to adapt them to changes in conditions, in the needs of the mining industries, and in the public interest; those current activities that contribute most to problem of present concern are emphasized, investigations of less immediate importance being recessed, if necessary.

Jan 1, 1940

By G. W. Grove, H. R. Burdelsky, F. E. Griffith

"INTRODUCTION The work of using a system of air locks in unsealing a mine in Ohio following a fire probably was one of the outstanding jobs of its kind in a medium-thick coal bed.The fire in this mine, thought to have been of electrical origin, was discovered at about 1:30 a.m. on December 11, 1941. Forty-four men were working in the affected section at the time; 5 escaped unassisted, and 37, who had barricaded themselves, were rescued. The bodies of two men, who had succumbed after breathing fumes given off by the fire, were brought part way out of the mine before it became necessary to seal the mine.Direct attempts to extinguish the fire with water were abandoned when hazardous amounts of 'carbon monoxide, methane, and other inflammable gases were detected in return air passing through the main haulageway and escape-way of the mine.The mine was completely sealed on the surface at about 8 p.m. on December 12, 1941, with the two bodies remaining in the mine. Sixteen days after the mine had been sealed, the two bodies were recovered. This was accomplished by air-locking through a partitioned-off stairs compartment of a ventilation shaft. This work was done under adverse barometric and atmospheric conditions.A method for collecting representative air samples from the immediate fire area was used successfully by utilizing a vacuum pump on about 10,000 feet of existing water line that had been broken near the fire area.The immediate fire region was sealed, and confined to a relatively small area; the remainder of the mine was recovered, and operations were resumed February 9, 1942, or 59, days from the time of sealing the mine on the surface. This recovery was made by air-locking the main entries inby from the shaft and No. 2 right-face entries.The distance between air locks averaged about 500 feet, and as each new set of seal stoppings and air locks was completed, the old or outby seals were taken out and the area between was ventilated. In ventilating this area, it was often necessary to use line curtains to direct the air into dead-end places."

Oct 1, 1947

By William C. Miller

This report describes investigations by the Bureau of Mines designed to establish the noise level and spectrum of various types of pneumatic rock drills and to furnish information that would be useful in conducting sound measurements in mining environments and in reducing the noise generated in pneumatic drilling. These investigations show that (1) the noise generated by the drills in the frequencies below 100 cps is caused by the impact of the piston and drill steel, in the frequency range between 100 and 2,000 cps by the exhausting of air from the ports, and in the frequencies above 2,000 cps by the resonant frequencies of steel drill parts and of drill steel; (2) satisfactory instruments and instrumentation systems are available for field and laboratory measurements; (3) reliable sound measurements can be made in mining environments; and (4) devices can be developed that will abate the noise.

Jan 1, 1963

By C. P. Mangelsdorf

When the finely bedded shale frequently encountered over coal seams experiences a separation, the material below the separation must behave like a beam or plate in that it must resist both bending and shear. Be-cause of the weakness in interlaminar shear inherent in such strata, shear deflections that are usually ignored in isotropic beam theory may account for a significant part of the total roof sag. Similarly, when a roof truss is installed in such a roof the upward displacement reducing the sag will have components due to shear as well as bending. Questions asked by mine operators about the installation of roof trusses frequently deal with optimum position, slope, and initial tension of the inclined chords. This Bureau of Mines report examines the effects of those chord parameters on the strain energy of both shear and bending and offers optimum values that will minimize the total strain energy of the immediate roof. Design charts are provided, several design examples are included, and the results are compared with current practice. The effects of in situ stresses are investigated and are shown to be equivalent to an additional load on the beam.

Jan 1, 1988

By W. E. Young

This paper describes operations of the Chief Consolidated Mining Co. at the Chief mine in the Tintic district, Juab County, Utah, where the outstanding problem is water control; the unique pumping methods employed are featured in this report. The ore bodies in this district occur as long, narrow shoots along fault fissures, usually in the Bluebell dolomite of Ordovician age. Oxide ores predominate above the 1800 level, which is also the natural water level. Sulfide ores containing lead, zinc, silver, and gold extend below the 1800 level. The mine is developed by vertical shafts and winzes, from which drifts are driven to the ore bodies. In the lower levels of the mine these drifts extend long distances from the shafts or winzes because of the relatively low dip of the ore shoots. The mine has been worked to the 2800 level and the 18-411 winze extends to the 3080 level.

Jan 1, 1958

By J. E. Tiffany, Z. C. Gaugler

An active list of permissible explosives was published in December 1943 as part of the Bureau of Mines Report of Investigations 3736 under the title "Active List of Permissible Explosives and Blasting Devices Approved Previous to June 30, 1943." This list included 180 brand names. Changes in the list that have been authorized to December 31, 1945, placed 10 additional brands of permissible explosives on the active permis- sible list as a result of tests and changes in brand names.. Twelve permis- sible explosives were transferred from the active. to the inactive list. The present list contains 178 brand names. The brand names of the permissible explosives placed on the active list are as follows: American 3-A By test. Apcol No. 1-B Do. Black Diamond No. 11-B DO. Black Diamond No. 55 DO. Coalite G-1 DO. Coelite K-1 Do. Do. Coalite L-1 Coalite IS-1 Columbia B-2 DO. By change in name. By test. Monobel AA The permissible explosives transferred from the active to the inactive list are as follows: Anthracite B, L. F. Big Red No. 8 Independent No. 1, L. F. Independent No. 2, L. F. Independent No. 3, L. F. Independent No. 4, L. F. Independent No. 5, L. F. Independent No. 9, L. F. Independent No. 9-C, L. F. Independent No. 10, L. F. Independent No. 11, L. F. King No. 9

Jul 1, 1946