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By R. S. Lang, C. C. Merrill

The recovery of zinc from oxidized zinc minerals by the caustic soda leach and electrolytic or chemical precipitation was investigated . With the exception of willemite ( 2 ZnO • Si0₂ ) oxidized zinc minerals were readily soluble in 180 to 240 g / 1 NaOH solutions . A high- grade zinc flake was recovered electrolytically from solutions which had been treated with zinc powder to precipitate copper and lead . Solutions were recycled to the leach stage with a recovery of about 85 percent of the zinc from an ore containing 21.2 percent zinc . Electrolysis was conducted at a current density of 120 amp / ft2 with a power consumption of about 1.5 kwhr /lb zinc . Zinc was also recovered from leach solutions by dilution of the solutions , carbonation of the solution , or the addition of sulfur to boiling solutions . A dilution ratio of 5 : 1 precipitated 59 percent of the zinc in 9 days . Carbonation of the solutions precipitated the zinc as zinc oxide ( ZnO ) and solutions could be recausticized for recycling . Zinc precipitated as the sulfide with sulfur was easily filtered and washed . Approximately half of the sulfur added to solutions was lost in the form of sodium thiosulfate ( Na S₂03 ) .

Jan 1, 1965

By J. H. Daniel

This report, summarizing the results of two studies sponsored by the Bureau of Mines, presents information on the types of mobile machines used in surface coal mines in the United States, and the amount of noise to which miners are exposed. Data consist of a calculated value of the probability of noise overexposure caused by specific equipment. These data are extrapolated to estimate the number of overexposed operators. Bulldozers were identified as the major contributors to noise overexposure, and the report presents results of a Bureau-funded program on the feasibility of providing retrofit noise control on bulldozers.

Jan 1, 1980

By F. D. Everett

The Burgin shaft of Bear Creek Mining Co. near Eureka, Utah, was sunk during 1956 and 1957 as part of an exploratory program, searching for lead, zinc, copper, silver, and gold ore bodies hidden from the surface by several hundred feet of volcanic rocks. This paper describes the sinking methods and operating practices of Centennial Development Co., contracting firm for Bear Creek Mining Co., in sinking a 3-compartment vertical shaft 1,100 feet. The operation featured the Cryderman positive-action, clam-type shaft mucker. The shaft was completed in 142 days by a shaft crew of 10 men and a top force of 10 men, including supervision.

Jan 1, 1959

By E. Kamon

This report summarizes completed research pertaining to the reaction of human subjects exposed to Self-Contained Breathing Apparatus (SCBA) stressors during escape conditions (viz., resistance breathing, C02 breathing, hot air breathing, and static positive facepiece positive pressure breathing) and the development of an automated breathing and metabolic simulator (ABMS). Volume I contains summarizes of the studies performed under this contract. Volume II is an appendix which contains more detailed descriptions of these studies.

Jan 1, 1984

By Donald H. Koch

The project investigated the impacts of coal and mineral storage piles on both ground and surface water quality. The study consisted of two major tacks, Task 1 had two phases. The first phase was field investigations in which ten cons and mineral stockpile sites (5 coal, 5 mineral: phosphate, lead, copper, iron, uranium) across the country were visited to determine the actual impart of coal and mineral stockpiles on writer quality. The second phase of Task I was a series of leaching experiments in which drainage from the ten coals and minerals was controlled and monitored to survey the extent to which storage piles release toxic ions to ground and surface waters. Task IT was n review of pollution abatement techniques with three generic treatment examples applied to lead-zinc ore, eastern coal, and uranium ore stockpile leachate. Major conclusions drawn from the completion of Tasks I and II include: water quality impacts are site specific, there is n high correlation between sulfide content of u material and its solution potential, and the selection of the best treatment alternative for n specific coal or mineral storage area must be based on site-specific criteria, pilot studies on representative leachate samples, and sound engineering design.

Jan 1, 1982

By L. K. Barker

The purpose of this research was to determine how much, if any, improvement would be made by subjecting hydrogenated shale-oil naphtha to a catalytic reforming process. Preselected ranges of temperature and pressure within the commercial reforming ranges were chosen for investigation and other possible variables were held constant. All tests were made with a liquid hourly space velocity (LHSV) of 3 volumes of liquid feed per volume of catalyst per hour (Vf/Vc/hr) and a hydrogen feed rate of 3,000 scf/bbl. Operating temperatures of 850°,875°, and 900° F were used at pressures of 200,400, and 600 psig. The greatest octane improvement in the naphtha was obtained at a temperature of 900° F and pressure of 200 psig. The reformed naphtha had a clear research octane number of 89, a liquid yield of 80 vol pct, and a yield-octane number of 71.1. The data indicate that a higher temperature could have produced a higher yield-octane number.

Jan 1, 1973

By J. R. Thoenen

This circular is part 6 of the third paper (entitled "Excavation") of a series summarizing the technical problems involved in the production and preparation of sand and gravel. Part 1 discussed the use of power shovels, draglines, and excavator cranes; part 2, power scrapers, slackline cableway excavators, and hydraulic monitors; part 3, hydraulic, clamshall, ladder, and diaper dredges; part 4, haulage equipment, particularly industrial cars with locomotive or hoist as the motive power; part 5, conveyor belt, motor truck, pump and pipe line, towboat and barges, and aerial-trams haulage. This circular discusses the application of these various types of equipment to the different types of sand and gravel deposits and contains a reference bibliography. It completes the discussion of excavating problems.

Jan 1, 1936

By Ned H. Snyder

In recent years the Government and other large consumers of coal have appreciated more and more the desirability of definitely determining by chemical analysis and test the character and quality of the coal they purchase. Higher prices for coal point forcibly to the need of giving more study to engine room and boiler room efficiencies and economies; this implies an intimate knowledge of the character and quality of the fuel used. Analyses and tests of delivered coal furnish data whereby power plant results can be comprehensively studied and a continuous check maintained on the coal and on the conditions of plant operation. Under authority of acts of Congress making appropriations for technologic investigation of fuels and the analyzing and testing of fuels belonging to or for the use of the United States Government, a laboratory is maintained at the Pittsburgh station of the Bureau of Mines, where samples representing deliveries of coal purchased for Government use are analyzed and tested.

Jan 1, 1923

By Allan E. Martin

As part of a comprehensive investigation of tae mechanism of desulfurization of iron and steel by slags, the Blast Furnace Studies Section, Metallurgical Division, Bureau of :lines, in cooperation with the Institute of Technology., University of Minnesota, has made a study of the forms in which sulfur occurs in blast-furnace slag. This report presents data on the three sulfides most important in iron smelting, namely, ferrous sulfide, manganous sulfide, and calcium sulfide. The tendency of these sulfides to form colloids in the molten slag was determined by an examination of quenched samples with an ultramicroscope. Vogt5/ conducted experiments on sulfide silicate melts and examined synthetic blast-furnace slags in a partly crystallized condition. His conclusions were that FeS, CaS, and MnS, or isomorphous compounds, such as (FeXCay)S and (MnxCay)S, were precipitated from the melt, depending on the composition of the slag. In all specimens sulfides were visible and were spherical.

Jan 1, 1941

By Dana T. Updyke

The objective of this project was to develop technical data and evaluate performance and utility of leaky feeder communications systems currently used in North American underground mines. The desired information was obtained principally through on-site surveys. Altogether, six of the seven mining companies known to be using leafy feeder communications were visited. This report covers the findings of these surveys. In addition, the report provides a brief background summary of mine communications, a technical discussion of leaky feeder systems, and conclusions and recommendations based on the results of the survey.

Jan 1, 1980

Three complete connector assemblies and ten separate contacts were submitted to a series of tests to establish the connector permissibility and compliance with the Bureau of Mines' research Contract H 0110423. Test Procedure TPC-0100 was coordinated, and the test plan approved by the Bureau as fully complying with the intent of the contract for the low voltage, medium voltage and high voltage A.C. connectors. The components and connector assemblies have been demonstrated in testing that they meet or exceed all the requirements of the test procedure.

Jan 1, 1972

By Jesse J. Brown

Over 60 simple; were prepared and forwarded to Dr, S. Z. Toma, TPO, PMSRC as a result of this project. Included among these samples were various low temperature forms of silica. Samples of quartz, cristobalite, and tridymite with iron, manganese, and titanium impurities present were prepared. In addition, a long series of samples both wet ground and dry ground for times from 1/2 to 8 hours were prepared. Numerous miscellaneous samples were submitted which included kaolinite, calcite, muscovite, illite, montmorillonite, Ba3(P04)2, and YPO4 among others, in response to special requests from the TPO. The silica rich portion of selected binary (CA 203-Si02, In 203-Si02, Li20-Si02) Na20-Si02, PbO-Si02, SnO2-Si02, Sn02-Si02 BaGa204-SiO2 and SrGa204-Si02) and ternary systems (Na20-Ga203-Si02 and Li20-Ga203-Si02) was investigated to determine the effects of solid solubility on the stabilization of the high temperature forms of tridymite. In addition to the determination of the extent of these crystalline solubilities, observations were made. on the mechanism of the transformation of silicic acid to tridymite and the rate of the reaction in the presence of foreign ions,

Jan 1, 1973

By Jeffrey Shawn Peterson

The testing procedures of the u.s. Mine Safety and Health Administration specify that intrinsic safety acceptance tests be conducted using a standard tungsten-cadmium electrode configuration in the break-flash apparatus. However, in realistic mining environments, other materials may be more likely sources of sparking. Information defining the probability of spark ignition between common materials such as aluminum, brass, copper, lead, tin, cold-rolled steel, and stainless steel is of more practical value in determining ignition hazards. The U.S. Bureau of Mines has completed an investigation of the influence of material on the ignition probability using the breakflash apparatus. By comparing ignition currents or ignition voltages corresponding to a probability of one ignition per thousand sparks to those found previously for cadmium, a margin of safety may be estimated for each material. This report presents the results of an investigation into the influence of disk electrode material on the probability of ignition.

Jan 1, 2010

By H. L. Burmeister

This is one of a series of publications by the Bureau of Mines dealing with mining methods and costs at representative operations in the United States. The report describes all phases of the mining methods for the open-pit operation and milling practices employed at the Vermont Asbestos Mines in Lamoille and Orleans counties, Vermont. A brief history of discovery and development of these asbestos deposits is given, and the ore deposits are described. Methods employed in exploration, sampling, and estimation of tonnage and grade are outlined. A breakdown of available cost figures is summarized in the last section. All asbestos ore produced in this area has been won by the use of surface-mining methods. Two quarries, the Lowell and the "C" Area, are in operation. The quarries combined are producing and the mill is processing approximately 3,500 tons of ore per 3-shift day The average 40,000 tons of crysotile asbestos fiber produced at this plant annually accounted for 96 to 98 percent of the total fiber produced in the United States in 1958. The mine is located (fig. 1) approximately 4 miles north of Eden Mills village on the southeastern flank of Belvidere Mountain (fig. 2).

Jan 1, 1962

By J. R. Thoenen

Up to 1914 almost all of the world's supply of potash came from Germany and Alsace. With the cessation of shipments from Germany during the World War the importance of a domestic supply was evident, During the past 15 years the United States has been working toward the establishment of a domestic potash industry which would end foreign dominance in this commodity. The Federal government has taken an active part in this program. As its share in the work, the Bureau of Mines has ascertained the potash resources in certain districts through core drilling and has engaged in a comprehensive program of research on the extraction of potash from its various minerals. Until the passage of the Winter bill (H. R. 496) by Congress in 1928 the Bureau of Mines had not been able to give any consideration to the western ores, wyomingite (leucite) and alunite. With the Passage of this bill, however, the ray was opened for the extension of the potash studies to cover these materials.

Jan 1, 1932

By Walter J. Frank

The purpose of the work covered by this contract is to develop a means of designing splice connectors which will significantly improve mine trailing cable splice performance. A brief discussion on splice problems is presented as an introductory means and substantiates the need for the development and test programs outlined in this report. Because of the empirical nature of this effort, time has been devoted to explaining the derivations of the test procedures used. Special attention is given to the splice flexing machine which served as the backbone of the test program. In order to familiarize persons with connector terminology, a section is devoted to a glossary of pertinent terms. Various types of cable joints are also defined. The major effort is a connector design parameter study. Utilizing the optimum parameters developed along with the suggested design procedure outlined in Appendix I should result in significantly improved splice performance and thus meet the objectives of this contract. A field test program was instituted for the purpose of insuring adaptability of connector design and associated installation tooling along with a field performance study. During the course of work, other significant factors affecting splice performance were uncovered. Although not covered by the scope of this contract, a brief discussion is presented for the purpose of stimulating interest in what is considered other fruitful areas for improved splice performance.

Jan 1, 1976

By C. E. Dobbin

The coal fields of Montana are widely distributed through the plains region in the eastern and northern parts of the State, and the mountain regions in the central, southern, and southwestern parts of the State. (See fig. 1.) SURFACE FEATURES The Fort Union region in eastern Montana is a broad plain of almost horizontal rocks, characterized by extensive "bad lands" along the larger streams and by red hills, benches, ridges, and buttes which represent shale and sandstone that have been fused by the burning of an underlying coal bed.

Jan 1, 1932

By Mary L. Pearson

Ibis report summarizes the results of the contract. Included are summaries of existing legislation pertaining to outcrop barriers and a state-of-the-art survey of outcrop barrier designs and related, mine closure techniques. Six sites were inspected in the field and are presented as case histories The data analysis presented includes a computer modeled seepage analysis, an overburden blew-out analysis, and a wedge stability analysis. The results tit these analyses are interpreted to form recommendations for coal outcrop barriers which will minimize seepage and the potential for failure. Supplementary support and reinforcement alternatives are also discussed.

Jan 1, 1981

By Shiro Watanabe

To determine the potentialities of nickel as a substitute for cobalt in catalysts for the synthesis of hydrocarbons from carbon monoxide and hydrogen, RESULTS The maximum oil yields obtained in bench-scale equipment were as follows: Using 100N1:20Mn:100 kaolin:200 diatomaceous earth catalyst, a maximum yield of 133.8 cm.3/m.3 of pure CO+2H2 was obtained from one pass of the feed gas, With a nickel:cobalt mixed catalyst (Ni:Co - 3:7) having the composition 100(Ni+Co):8MgO: 5Th02:200 diatomaceous earth, a maximum of 172.2 cm.3/m.3 of pure C0+2H2 was obtained.

Jan 1, 1951

By P. Wearden, K. Bryner, K. Vrana, V. Castranova, R. Dey, R. Reist, J. Blackford

"Summary: Fibroblast proliferation and enhancement of collagen synthesis are key steps in the development and progression of pulmonary fibrosis. The current investigation presents a fibroblast proliferation assay to detect the release of competence factors from pneumocytes. The specific objective of this study was to define cell culture conditions for fibroblasts that would allow selective detection of competence factors in test media. The results indicate the following: (a) fibroblasts should be cultured for 2 days in plasma-free medium rather than 2% plasma to assure complete quiescence; (b) 1% plasma was optimum for producing progression activity for the bioassay of a competence factor, while 0.5% plasma did not produce sufficient progression activity (yielding false negatives) and 2% plasma often contained significant competence activity (yielding false positives); and (c) fresh plasma should be used since the progression activity of plasma was adversely affected by freezing and thawing. Under these conditions, this bioassay can be employed with either rat or human lung fibroblasts to detect competence factors such as platelet-derived growth factor (PDGF), at levels as low as 25 ng/ml.Fibrotic lung disease, as a consequence of occupational exposure to silica dust. is characterized by the development of concentric hyalinized nodular lesions in the lung and the progressive loss of pulmonary diffusion capacity. Proliferation of pulmonary fibroblasts and enhanced synthesis of collagen by these pneumocytes have been shown to be key steps in the development of chronic silicosis ( 1 ). The regulation of lung fibroblast proliferation by cytokines released from alveolar macrophages may be an important pathogenetic mechanism in the development of the fibrotic process (2). Some cytokines stimulate fibroblast proliferation by activating specific phases of the cell cycle (3,4). In particular, platelet-derived growth factor (PDGF) promotes fibroblast proliferation by inducing the movement of quiescent (G0 ) cells into the G1 phase of the cell cycle (5). Insulin-like growth factor (IGF) and transforming growth factor-P (TGF-P). on the other hand, regulate the rate of transition of fibroblasts from G 1 into the S phase (5,6). These two classes of cytokines have been termed competence and progression factors, respectively. One approach used to examine the release of cytokines from macrophages is the fibroblast proliferation assay in which quiescent fibroblasts are exposed to culture supematants from macrophages exposed to various stimuli. In most of these assays, the supernatant contains fetal calf serum (FCS), which provides the competence factor(s) necessary to facilitate the proliferation of fibroblasts (7-9). Recently, a fibroblast proliferation assay using platelet-poor .plasma [lacking competence factor(s)] as a substitute for FCS bas been described (I 0, 11 ). In this assay, the release of a competence-inducing PDGF-like growth factor from rat and human macrophages can be distinguished from other cytokines that act as progression factors."

Mar 1, 1992