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By M. M. Fine

A preliminary mineral-dressing study of five samples of East Texas limonitic brown iron ores was conducted as part of the Bureau of Mines program to develop and extend domestic resources of iron ore. The samples were considered to be typical of ore currently being mined and beneficiated by the Lone Star Steel Co. and Sheffield Steel Co. The objective of the research was to investigate those mineral-dressing unit operations that might recover some of the fine iron lost in current industrial wastes or perhaps improve the recoveries when applied to the ores as well. Since current industrial beneficiation practice yields a washed limonite analyzing 41 to 45 percent iron, higher grade concentrates were not sought in this laboratory study. Laboratory investigation included washing and sizing, reduction roasting, and subsequent magnetic separation of the finely ground roasted materials. The results showed that laboratory recoveries of over 80 percent of the iron were possible, for the ores investigated, at concentrate grades comparable to those expected from cur-rent industrial beneficiation practice. ACKNOWLEDGMENTS Acknowledgment is made to the Lone Star Steel Co. and Sheffield Steel Co. for supplying the brown iron-ore samples on which this research was conducted.

Jan 1, 1956

By Aner W. Erickson

Magnetite iron deposits on Tolstoi Mountain were examined as part of the investigations by the Bureau of Mines of iron and copper ores on Prince of Wales Island. The Tolstoi Mountain project was a part of a program for investigating mineral deposits in Alaska, under the general supervision of R. S. Sanford, acting branch chief.

Jan 1, 1948

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 Kenneth M. Earl

In its investigation of deposits of strategic minerals, the Bureau of Mines did some diamond drilling at the Almedia deposit In an endeavor to find an additional source of supply of lead and zinc. It is reported that in 1816, lead and zinc minerals were found in the limestone quarries near the boundary line between Scott and Center townships. In an attempt to develop these minerals in paying quantities, an alit was driven for several rods into a bluff Just west of the present Almedia mine, This is believed to be the Web mine, mentioned briefly by Parker Cleaveland in 1816. In 1901 the Almedia mine was developed by an open cut and three shafts. The hoisting shaft at the time of drilling by the Bureau of Mines was sounded to a depth of 115 feet. A concentrating plant reportedly made shipments to Hamburg, Germany, for reduction. The deposit is in a somewhat slaty limestone. The ore occurs in a northeast fracture zone along the strike of the limestone and dips to the southeast. Old miners state that the ore appeared as large chunks of galena and sphalerite. In 1949, to investigate the downward extension of the oreshoot, the Bureau of Mines drilled four holes aggregating 1,126.3 feet.

Jan 1, 1950

By C. W. Vierrether

Tailings from the Pea Ridge iron mine contain significant amounts of apatite, which has rare-earth element values associated with it. In association with the recovery of rare-earth minerals as a secondary resource, the U.S. Bureau of Mines conducted an investigation on the recover ability of the rare-earth minerals from these tailings. The mill tailings were subjected to a phosphate flotation to separate the apatite from other constituents. More than 70-pct recovery of the rare-earth values was achieved. Based on mineralogical characterization and prior analysis of rare-earth-bearing breccia pipe material at Pea Ridge, it is proposed that processing this phosphate concentrate on a vanner table would yield up to a 95-pct recovery of the rare earths in the concentrate, with the apatite reporting to the tailings. Intensive ore microscopy studies of the original tailings to the flotation products led to the identification of monazite, xenotime, and rare-earth-enriched apatite as the major rare-earth-bearing minerals in the tailings.

Jan 1, 2010

By T. E. Swigart

In the production of oil end gas, engineering methods have been applied less than in any other branch of the oil industry. While refineries, gasoline plants, pipe-line and other transportation systems, and even drilling wells to a great extent, take advantage of engineering skill, the tendency has been to assume that the handling of producing wells is merely a mechanical and routine matter. At present few companies employ engineers to study oil and gas production methods with a view of increasing the general efficiency of recovery, but in vie, of the advancement in other lines of the petroleum industry by the application of engineering principles, does it not seem likely that the production branch may benefit also by engineering studies? Engineering applied to the handling of producing wells falls under two general headings, - first, the efficient handling of wells from the time of their inception in order to obtain the greatest possible ultimate production, and, second, the rehabilitation of old properties that have been handled carelessly in their early lives. To date, the engineering work that has been done on oil production problems falls mostly in the second class. For example, the use of vacuum and the application of compressed air have proved successful in some instances in stimulating wells of low gas pressure. These methods are costly to apply and are adapted to small wells in which the gas is almost exhausted, or in which the original gas pressure is negligible. The experiments described in this paper fall under the first heading, as they were made with an idea of learning toe probable extent to which the gas production of an oil well can be curtailed while gas in the sand is still plentiful, and thus saved for doing work during the later period of a well's life. Because of the scope of the experiments, this paper does not include a discussion of back pressure on flowing wells or for purposes other than cutting down the gas produced with each barrel of oil.

Jan 1, 1922

By W. A. Stickney

As part of a Bureau of Mines program to investigate recovery of manganese (Mn) from low-grade materials, laboratory studies were made of four samples of mill rejects: Three from Montana and one from Peru. These studies demonstrated that certain mill-waste products can be a potential source of manganese. Both manganese oxide and carbonate minerals were recovered by flotation in an acid circuit with a fuel oil-tall oil emulsion as collector. Sintering) required to prepare a physically acceptable product, also was used as a method of beneficiation. In addition to being low-grade, some of the samples presented problems of intimate mineral association and complex textures.

Jan 1, 1960

By M. H. Stanczyk

The Bureau of Mines made bench-scale laboratory tests on a sample of typical Florida phosphate slime to determine alumina and phosphate extractions obtainable by agitation leaching, by baking and curing, and by a leach-electrolysis scheme. Recovery of mineral values from leached slime pulps by resin-in-pulp ion exchange contact and the reaction of the leached pulps to filtration, flocculation, and settling were also investigated. The best extractions of alumina and phosphate were obtained by (l) agitation leaching with sulfuric, hydrochloric, or nitric acid at an elevated temperature or (2) curing or baking the slime with sulfuric acid. Alumina extractions ranged from 80.8 to 90.0 percent and phosphate extractions ranged from 93.3 to 98.4 percent when the slime was leached at 90° C with sulfuric, hydrochloric, or nitric acids. Baking the slime with sulfuric acid at 200° C for 4 hours yielded an alumina extraction of 92.3 percent and a phosphate extraction of 97.0 percent, whereas curing with sulfuric acid at 100° C for 24 hours gave slightly higher alumina and phosphate extractions. Flocculation and settling properties of the slime were virtually unaffected in all cases. Filter area requirements, although somewhat improved as compared to untreated slime, remained relatively high. The lowest filter area requirement obtained was 44 square feet per ton of dry solids treated per day. Contacting leached slime pulps with ion exchange resins depleted the leach pulps of solubilized values; however, the filtration and settling properties of the barren pulps were unaffected. A leach-electrolysis scheme resulted in some concentration of solubilized phosphorus, but the method showed little promise of being commercially feasible.

Jan 1, 1966

By J. Koster

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.

Jan 1, 1939

By A. S. Peck

This report presents the results of a cooperative study between the Bureau of Mines and the University of Utah to define the mechanism involved in the adsorption of oleic acid and sodium oleate on fluorite, calcite, and barite, using an infrared spectrophotometer for identifying and measuring the adsorbed reagents and reaction products. Fluorite, calcite, and barite react with oleic acid and sodium oleate in a water system, forming chemisorbed and solution products. The chemisorbed species is a surface mineral cation-collector anion salt, Chemical analysis of solution resulting from the adsorption reaction indicates that the adsorption process causes displacement of mineral anions, namely, fluoride, carbon ate, and sulfate from the surface of these minerals.

Jan 1, 1963

By C. W. Smith

Research was conducted to evaluate the effectiveness of a well-point dewatering system in conjunction with a french drain to intercept waste impoundment leakage while reducing the volume of waste water requiring treatment. A well-point dewatering system composed of 585 production wells was installed around the perimeter of a leaking impoundment that previously used only a french-drain system for leakage control. The placement of the well-point system was designed to intercept and remove the leakage from the groundwater before the contaminant reached the french drain. Groundwater monitoring at this site revealed that after a period of approximately 40 days the well-point dewatering system had stabilized and effectively prevented the further spread of contamination to the french drain.

Jan 1, 2010

By Michael G. Zabetakis, Israel Liebman, Henry E. Perlee

Flammability studies conducted to date on stratified methane - air and pentane - air mixtures in air indicate that location and extent of a flammable layer are affected by molecular diffusion , gas motion , and propagation of flame . In initially quiescent mixtures , the lower limit - of - flammability zone may be determined by assuming molecular diffusion alone governs mixing rate . The upper limit - of - flammability zone can be predicted in this manner only for stratified layers with small concentration gradients ( less than 0.2 volumepercent per inch ) ; where large concentration gradients are encountered ( for example , as much as 30 volume - percent per inch ) , the initial - mixture methane concentrations that yield flammable mixtures are larger than anticipated . Flames propagating through heterogeneous quiescent methane - air atmospheres in the direction of the concentration gradient exhibit flame speeds at any point that corresponds to the flame speed of the homogeneous gas mixture having the same gas composition as that of the point in the heterogeneous system . In flowing mixtures with large concentration gradients , the degree of mixing prior to ignition does not appear to affect the flame velocity and emitted radiation appreciably in a 6.5 - ft - diameter gallery .

Jan 1, 1964

By R. L. Hopkins, H. T. Rall

A continuous method has been developed for preparing thiolacetic acid . Acetic anhydride and hydrogen sulfide are passed concurrently over an amine ion- exchange resin , under 20 - psi pressure . The thiolacetic acid , a product of the reaction , is flashed continuously from the crude reaction mixture and is purified by fractional distillation . The yield of thiolacetic acid is in excess of 80 percent based on the acetic anhydride charged . INTRODUCTION In the synthesis of reference compounds needed in the identification of sulfur compounds in petroleum , thiolacetic acid has become an important reagent because of its use in the synthesis of thiols by addition to appropriate olefins : R - CH = CH₂ + CH3 - COSH R- CH2 - CH2 - S - COCH R - CH2 - CH₂ - SH + CH3COONa NaOH (1 ) The commonly used procedures for its preparation , as described by Clark and Hartman (1 )4 and by Ellingboe (2 ) , are based on the batchwise reaction of acetic anhydride with hydrogen sulfide :

Jan 1, 1964

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

By Joan K. Kuenzi

The purpose of this U.S. Bureau of Mines information circular (Ie) is to discuss how job analysis methods taken from different disciplines can be used together to form a more complete picture of jobs in the mining industry. "Job analysis" is a term used by many researchers, but use of the term is far from standardized. Authors of papers on this subject often state that there is confusion in how or why jobs are to be analyzed, what the resulting information is to be used for, and what the "job analysis" actually means. The process of breaking a job into elemental tasks and analyzing them is used to determine what skills and knowledge are needed to perform a given job, to improve efficiency, and to develop safer job procedures. All are valid reasons to analyze jobs, but the methods used to accomplish the analyses may be very different. In order to create a more complete picture of a job, it may be useful to incorporate methods and information from different areas of study rather than choosing one method for analysis.

Jan 1, 1995

By V. A. Nieberlein

An extractive process was developed applicable to submarginal titanium deposits containing valuable minor constituents; such as columbium (niobium) and iron. The process consisted of reducing the mineral concentrate with coke at high temperature to form a carbide-suboxide sinter, chlorination in the 400° -500° C. range, and fractional condensation of the chlorides. The chlorination procedure recovered 97, 83, and 87 percent of the titanium from brookite, rutile, and ilmenite sinters, respectively, while simultaneous columbium recoveries on the same materials were 85, 50, and 87 percent.

Jan 1, 1957

By J. C. Edwards

To have the capability to predict the development of localized spontaneous heating within a porous coalbed that is subjected to forced air ventilation or in an otherwise quiescent environment in which buoyancy develops, the Bureau of Mines developed three time-dependent mathematical models, which were used to calculate the temperature increase associated with chemisorption of oxygen by the coal. In each model, spontaneous heating is driven by an Arrhenius first-order reaction between the oxygen and coal. Two models are two-dimensional, and one is one-dimensional. In the first two-dimensional model, a constant-velocity forced convection airflow is specified; and in the other, buoyant flow is allowed to develop in the absence of forced convection. The third model evaluates the airflow from Darcy's law and a specification of the pressure at the surface of a one-dimensional porous coalbed. Numerical computations demonstrated how each model could be used to predict the onset of spontaneous heating when the porous coalbed was subjected to constraints of an imposed internal heat source or a high temperature airflow. The effects of particle size and coalbed compaction upon spontaneous heating were examined with the third model.

Jan 1, 1990

By Peter N. Gabby

In 1990, the Bureau of Mines conducted a mineral resource investigation of the 12.321 acre Black Warrior study area, one of several proposed additions to the Sawtooth Wilderness. No identified mineral resources were delineated. There were 123 lode and placer claims in or adjacent to the study area. There is a known hot spring adjacent to the study area, but presently no geothermal leases are pending. Lode mines in pr adjacent to the Black Warrior study area have produced 4,022 tons of ore from which 1,981 oz of gold and 811 oz of silver were recovered. None of the vines are currently active. During the field study 125 rock samples were taken. Significant gold assays and favorable geologic characteristics at seven properties indicate that gold occurrences and resources with byproduct metals may exist in the study area. Two other sites yielded anomalous gold assays; however, sage favorable geologic characteristics are lacking. Presently, identified gold resources are being delineated by drilling programs in the nearby Atlanta and Rocky Bar mining districts. These districts have geologic characteristics similar to the Black Warrior area. During the field study 22 placer samples were taken. In most places where an anomalous concentration of gold was found, the stream channels are too narrow for operations other than recreational suction dredges. However. One area is estimated to contain over 2 million yd3 of gold-bearing gravels.

Jan 1, 1992

By Kathleen M. PH. D. Kowalski

This paper discusses human judgment and decision-making under stress. The authors review selected recent literature across various disciplines and suggest a definition of stress within the context of decision-making during the management of emergencies. They also discuss fieldwork by the Pittsburgh Research Laboratory, NIOSH, which explores traumatic incident stress, the relationship between previous training and performance under stressful conditions, and human behavior in underground mine fires. The authors assert that stress is one of the factors that decision-makers must contend with in most life-or-death situations. They suggest that a better understanding of individual's judgment and decision-making activities while under stress would yield a better understanding of how people reach the choices they make in emergencies. This enhanced understanding would be of enormous value to emergency managers, researchers, and policymakers.

Jan 1, 2008

By David E. Siskind

The Bureau of Mines studied environmental blast effects in six occupied residential structures. Airblast, ground, and structure vibrations were measured both inside and outside residences for seven quarry production blasts. Walls and floors responded to the blast noise and vibration by shaking at their own natural frequencies, often with greater peak particle velocities than the ground outside the structures or their foundations. The vibrations of the houses generated noticeable internal noise, correlating with the arrival of the groundborne energy. The later arriving airblast wave was predominantly at low infrasonic frequencies (1.0 to 1.5 Hz) and had similar amplitude and frequency characteristics both inside and out-side the structures. Significant structural motions resulted from the air-blast overpressures for at least two of the seven blasts. The most severe airblast effect occurred at a house 1,800 feet from a 5,047-pound (200-lb/ delay) blast. This stucture was subjected to a peak 0.16-in/sec particle velocity and 130 dB(L) airblast. The wall of the second floor responded to the ground vibration and airblast by shaking at particle velocities of 0.15 and 0.28 in/sec, respectively. Analysis of these data and those from additional field studies will be used to identify appropriate, safe, and reasonable impulsive noise levels, measurement techniques, and factors of design applicable to minimizing the adverse environmental effects of blasting.

Jan 1, 1976