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By F. J. Palumbo

Effective recycling or disposal of flue dusts is a continuing problem for copper, brass, and bronze smelters. Over 300,000 short tons (st) of dust is generated annually by U.S. secondary copper, brass, and bronze smelters. The Bureau of Mines has developed an alkaline leach method for recovering metal values from copper converter flue dust containing zinc, tin, lead, and copper. The dust was leached with a hot solution of ammonium chloride and ammonium hydroxide to solubilize ZnO. All of the tin (as Sn02) and the metallic copper, lead, and zinc, as well as possible insoluble compounds of each, report to the residue. Dissolved copper and lead salts are removed from the leachate by cementation with granular zinc. Zinc oxide is precipitated by diluting the leachate with water. The tin-rich (9.8 pct) residue has a ready market. The cement product is recyclable to the smelting operation. The ZnO is at least 97 pct pure and has potential marketability.

Jan 1, 1985

By D. Harrington

"In order to stimulate general interest in mine safety among their employees the mining companies of Butte, Mont., instituted in 1918 a Miners' Field Day, and this field day has since been held annually about the end of July, the last one being on July 25, 1921. The mining companies of the Butte district finance this meet in proportion to the number of men employed at the time of the meet, the contributing companies with number of working force, end proportional contributions for the opening field day in 1918 being given below:COMPANY NUMBER EMPLOYED AMOUNT CONTRIBUTEDAnaconda Copper Mining Co.,12,500,$ 1,078.53Butte & Superior Mining Co.,1,800,155.32North Butte Mining Co.,,1,294,111.67East Butte Copper Co.,,850,73.36W. A. Clark Interests,,600,51.78Davis-Daly Mining Co.,,340,29.35,,,,17,384,$ 1,500.00*Note: In many mining districts it is now the custom to hold an annual Miners' Field Day. The field day, as a rule, is financed principally by the mine operators, and was instituted primarily to promote interest among miners in the ""Safety First"" movement. Usually demonstrations or contests in first aid and mine rescue are the leading feature of the day's events, which include games, races, dancing, and all the other amusements usual to a gala holiday. Thus the field (ley serves the double purpose of stimulating interest in mine safety and promoting cordial relations and community fellowship. This paper is an interesting account of the way in which the Miners' Field Day in the Butte district is organized, with data on costs, plan of organization, method of conducting, and the practical benefits derived from it. - Ed"

Oct 1, 1921

By N. A. Tolch

[In this partner ?propulsive strength? or "strength" is defined as the relative propulsive effect of an explosive as determined by means of the United States Bureau of Mines ballistic pendulum. The data presented are derived from one particular strength testing device and do not necessarily represent the relative execution value of the different explosives in actual blasting. However, it is believed that the data obtained with the ballistic pendulum fire indicative of the relative propulsive or heaving force and are of value until propulsive strength can be expressed in more fundamental units.]

Jan 1, 1929

By F. E. Joyce

The Bureau of Mines studied copper-nickel minerals (mainly sulfides) of the Duluth Gabbro Complex in north-eastern Minnesota to determine their response to selective high-temperature sulfatization techniques. The gabbro, containing 0.44 percent copper and 0.13 percent nickel, was ground to minus 325 mesh and sulfatized in a heated, rotating, stainless steel bench-scale retort. Tests demonstrated that over 95 percent of the copper and 80 percent of the nickel can be converted to water-soluble sulfates, depending upon the roasting conditions employed. Yield equations were developed using regression analysis for predicting the extraction of copper and nickel between the temperature limits of 520° to 670° C, the roasting time limits of 3 to 7 hours, and S02 limits of 10 to 40 percent in S02-air mixtures.

Jan 1, 1971

By Greenwald, H. P

The Bureau of Mines has been conducting experiments on the explosibility of coal-dust in the experimental mine for more than 17 years. The results have been published from time to time3, and a forthcoming technical paper4 will summarize the results and discuss them in some detail. The present paper will be limited to a statement of the more important facts that these researches have discovered.

Apr 1, 1929

By R. V. Ramani, K. Bode

"IntroductionIn part 1 of this paper, the results of the experimental work in a wind tunnel under controlled conditions were presented. To understand the spatial and temporal behaviour of airborne dust under mine conditions, experiments were performed in the Lake Lynn Experimental Mine of the US Bureau of Mines. The mine airway experiments were designed to study the variations of ambient concentrations along the length of an airway, and the deposition rates and deposition velocities in an airway cross section. Other objectives of the study were to investigate the spatial and temporal behaviour of airborne dust with regard to air velocity and particle density, the size distribution of the airborne dust cloud as it travels in the airway, and the size distribution of the dust particles deposited along the airway. Other objectives of the study were to compare wind tunnel results with In-Mine results, whenever appropriate.Experimental ProcedureLocationA complete description of the Lake Lynn Laboratory Mine of the US Bureau of Mines (USBM) can be found in the US Bureau of Mines Information Circular 8911 (Mattes et al., 1983). This mine provides excellent facilities for dust experiments. The airway dimensions are similar to those of a coal mine airway. The mine has a drift (D Drift, see Figure 1) that extends almost 500 meters without interconnecting airways, stoppings, or bends. The D drift measures approximately 6m in width and 2,25m in height.The Lake Lynn Laboratory Mine· is ventilated by a variable speed, 75 kW (100 hp), 28,3 m3/s (60 000 cfm) blower fan installed on the top of the ventilation shaft. Air velocities of 1, 1,3 and 1,8 m/s, respectively, could be obtained in the D Drift. However, the temperature changes at the surface can cause small variations in air quantities and velocities underground. The low background dust level in the mine reduces the problem of sample contamination from other sources of dust. Extended periods of uninterrupted data collection can also be scheduled. Mine airway parameters which are important for the analysis include the dimensions of the airway and the ventilation data such as the air velocity, and the pressure loss in the drift. All these data were acquired during altimeter surveys which were conducted prior to each of the experiments."

Dec 1, 1995

By R. H. Sprute

Extensive Bureau of Mines laboratory testing has shown that electrokinetic densification can be an effective method for dewatering and consolidating unclassified metal mine mill tailings. The report describes results of a limited field test of this technique. Eighteen-cubic-yard concrete model stopes, 18 feet long by 6 feet deep by 56 inches wide, were filled with unclassified tailings slurry from a metal mine in the Coeur d'Alene, Idaho, district. Five different tests were performed. They showed that a strong, dense, dewatered fill can be obtained in a reasonably short time using electrokinetics, with typical power consumption of 25 to 30 kW-hr/yd3 of densified fill. At present power costs in the Coeur d 'Alene district, this would amount to 10 to 12 cents/yd3.

Jan 1, 1975

By W. A. Stickney

This report summarizes the results of laboratory tests of five samples of low-grade phosphate ores from Idaho. The laboratory test work has demonstrated that by grinding, desliming, and flotation a portion of the siliceous gangue can be removed. The highly carbonaceous ores responded successfully to treatment after preroasting, to produce a plus-30-percent-P205 product. It has been found that highly siliceous ores, as represented by the samples treated, are more readily amenable to concentration than ores high in calcium carbonate. Of the five samples tested, four were amenable to concentration to a product containing over 30 percent P205. One sample, from the Conda, second bed, was not amenable to mineral-dressing treatment to produce a plus-25-percent-P205 product.

Jan 1, 1955

By Claude A. Tongish

This Federal Bureau of Mines report presents information on the accumulation and distribution of helium in U.S. natural gas reservoirs. The investigation concerns the relationship or association of helium with geographic location, geologic age, reservoir depth, nitrogen, carbon dioxide, and argon. Although helium is a minor constituent in natural gas, these data show that certain conditions make some reservoirs statistically more favorable than others for the accumulation of helium. The report is based on gas analysis information collected-by the Bureau from 1917 to 1974 from 10,086 gas samples, representing 6,455 reservoirs in 35 States. The occurrence of helium in the reservoirs was 11.5 percent with less than 0.005 percent of helium, 70.9 percent with 0.005 through 0.29 per-cent of helium, and 17.6 percent with 0.30 percent or more of helium in the gas. Results of the various correlations are presented in tables and charts. Relationships have also been determined quantitatively by measures of correlation. The statistical data can be used to determine the environment under which reservoirs with high-helium contents are most likely to occur. These data can be used with other information for predicting the future helium resources of the United States.

Jan 1, 1980

By R. D. Wilson

Ten to twelve million tons of dust is produced by cement kilns annu-ally in the United States, resulting in a serious waste disposal problem. The Bureau of Mines investigated two alkali volatilization methods for converting this dust into materials for making portland cement and a useful potassium product. Portland cement kiln dust was found to be composed of finely ground cement raw materials (CaC03 and 8i02) having a layer of alkali sulfate (K2S04 and Na2S04). In this form, it cannot be directly recycled to cement kilns because concrete is weakened by a reaction between the alkali and the aggregate. Portland cements with 28-day strengths above 5,000 psi were produced from low-alkali residues using sintering and melting methods. For nearly complete removal of alkalies, primarily potassium sulfate, from cement kiln dust, a temperature above 1,300° C and a reducing atmosphere were required.

Jan 1, 1986

By C. W. Davis

Before listing the laboratories and the work performed there, it is proper to make clear what is done and what is not done by Federal bureaus, States, and Territories, as well as by countries to the north and south of the United States. FEDERAL Bureau of Mines. - The Bureau of Mines does not make assays or analyses for individuals or firms unless the samples are part of the ore-testing and ore-dressing investigations of the Metallurgical Division on representative ores from mining districts and of possible benefit to the entire mineral industry through published reports. All significant results obtained in this way are made public. Any mineral sample sent to this Bureau for simple identification will be examined.

Jan 1, 1938

By Lowell Stroud

A windowed-cell phase equilibrium apparatus was used to obtain equilibrium vapor- liquid data for a helium-bearing natural gas (Hogback) at temperatures from -100 to -250° F and pressures to 500 psia. Anomalous phase behavior resulting in the formation of two stable liquid phases occurred at tmperatures below -200° F and pressures above 200 psia. A review of the published literature on the occurrence of multiple-liquid phases included in the report indicates that the experimental results with Hogback gas are the first substantiated evidence of a vapor-liquid-liquid equilibria in a helium-containing natural gas.

Jan 1, 1963

By L. C. IlsLey, E. J. Gleim

It is the firm belief of the Bureau's engineers that the introduction of electrical mining machines has done much to increase safety in mining as a whole . There can be no doubt but that the substitution of machine mining together with permissible powder for the method of " shooting from the solid " has been the means of saving the lives of many shot- firers . Machine mining also leaves the roof in a better condition as lighter charges of powder are required to bring down the coal . Thus the danger from falls of roof are lessened . It is recognized that every effort should be made to prevent all accidents due to the use of electrical machinery but it is felt that any action tending to limit the use of such machinery would be a backward rather than a forward step in the safety measures laid out to decrease the hazards in coal mining .

May 1, 1920

By D. G. Lee

Diesel particulate matter (DPM) often contains small amounts of metal as a minor component but this metal may contribute to adverse health effects. Knowledge of the mechanism for particle formation as well as the size preference of the trace metals is critical to understanding the potential for health concerns. To achieve this, the size and the composition of each particle should be optimally measured at the same time. Single particle mass spectrometer (SPMS) would be the best tool for this objective. In this paper, we therefore will introduce new findings about the mechanism and distribution of the trace metals in DPM, derived from a study where an SPMS was used to analyze freshly emitted DPM. KEY WORDS : Single particle mass spectroscopy, Diesel particulate matter, Characterization, Metal contents

Jan 1, 2006

By R. V. Ramani, P. M. T. White, D. Sutton

This report was prepared by The Pennsylvania State University under USBM Contract No. G0111808. The contract was initiated under the Coal Mine Health and Safety Program. It was administered under the technical direction of DMSE, with Mr. G. R. Schottler acting as the technical project officer. Mr. J. A. Herickes was the contract administrator for the Bureau of Mines. This report is a summary of the work recently completed as part of this contract during the period June, 1971 to December, 1973. This report was submitted by the authors on March 31, 1974. The project personnel express their thanks to Dr. Jay Politzer, The Pennsylvania State University Computer Center for providing the subroutine POLITZ and function IFIND, to Dr. Ray Masters, Department of Architectural Engineering, for permission for the use of the GRID program and to Dr. Lother Weyher of Bethlehem Steel Corporation for providing coal data.

Jan 1, 1974

By Arthur M. Hartstein

The Bureau of Mines, through contract with Ultrasystems, Inc., obtained data on the oxidative degradative behavior of a number of materials used in coal mines. Tests were performed using a stagnation burner arrangement. Materials examined included those used in typical coal mining operations such as (1) polyvinyl chloride-containing materials. (2) neoprene compositions, (3) rigid foams (urethanes/isocyanates), (4) miscellaneous materials (including jute, fiber glass, and polyethylene), (5) coal, (6) fluids (phosphate esters, organic esters, oil-water emulsions), and (7) composites. The composite comprised a mixture of a phosphate ester fluid with (1) coal, (2) a representative polyvinyl chloride sample, or (3) a neoprene-type composition. A number of decomposition products are identified that could represent a potential health hazard to miners including HC1, CO, SO2 and H2S, if they were generated to exceed toxic levels.

Jan 1, 1974

By Robert L. Thorne

Cassiterite deposits on Sullivan Creek in central Alaska were investigated by the Bureau of Mines in the spring of 1943. Gold miners in the area have been recovering cassitorite each season as a byproduct of gold placer operations. Approximately 300 tons of tin concentrates have been shipped from the district. The deposits were sampled though trenches and small shafts. An average tin content of 0.28 pound per cubic yard was indicated. A detailed description of sampling methods and sample analyses is presented in this report.

Jan 1, 1948

By Oliver Q. Leone

The effect of oxygen content in the anode metal on titanium electrorefining characteristics was studied. Increasing quantities of oxygen in the anode resulted in increased anode scale formation, decreased anode and cathode current efficiencies, lower titanium recovery efficiencies, and higher oxygen content of the cathode products. The titanium electrorefining process performed best when the anodes did not contain more than 0.5 percent oxygen, although anode dissolution was recorded for alloys containing up to 25 percent oxygen. Back emf affords a useful index of an alloy to electrorefining.

Jan 1, 1965

By Edward G. Cunney

Track in underground bituminous coal mines was investigated, and technology was taken from other industries in order to obtain information on conditions that impair the safety and efficiency of the track and to develop guidelines and useful information on the construction, inspection and maintenance of mine track. Volume 1 contains information on the investigations, observed track conditions, useful technology from railroads and other industries, derivations of track condition descriptors and recommended limits, conclusions, and recommendations. Volume 2, Guidelines, contains recommended standards and practices for mine track. It includes the relation of track conditions to safe speeds; descriptions and limits for measurable track features such as gage; descriptions of conditions for track components that are normally not measurable, such as subbase soils; construction requirements and techniques, inspection requirements and methods; and methods for managing and performing track maintenance work. As a research product, it does not repeat the summary or derivations. Volume 3, Inspection Handbook, summarizes recommended standards and procedures from Volume 2 and provides related information for' ready reference by inspectors in the mines. As a research product to be used in mines, it does not repeat the summary, derivations or references.

Jan 1, 1977

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