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By B. B. Letson

The heats of formation of lithium chloride and lithium oxalate were determined with the aid of a Bureau-developed, glass Dewar-type solution calorimeter which uses thermistors as its temperature sensing element. Values obtained at 298.15° K were -98.38 ± 0.54 kcal/mole for lithium chloride and -329.02 ± 0.79 kcal/mole for lithium oxalate, using graphite as the standard state for carbon.

Jan 1, 1965

By John B. Knaebel

This paper is one of a series being prepared by the Bureau of Mines on mining methods and costs at various mines in the United States, Canada, and Mexico, and is a description of practice at the Edwards mine of the St. Joseph Lead Co. ACKNOWLEDGMENTS The cooperation and assistance of the officials of the St. Joseph Lead Co. in permitting publication of this paper and providing every facility for its preparation are gratefully acknowledged. Especial thanks are extended R. J. Mechin, manager, R. F. Mitchell, mine captain, and J. S. Brown, geologist, for their generous aid, and the assistance of W. H, Weijola, mine engineer in assembling some of the illustrations is deeply appreciated, The helpful suggestions of C. F. Jackson, principal mining engineer, U. S. Bureau of Mines, are gratefully acknowledged.

Jan 1, 1932

By J. W. Miller

Depletion of coals most suitable for metallurgical fuel has made necessary a general survey of coking coal reserves in the United States. These investigations were begunn 1948 at the joint request of the Munitions Board, Department of Defense, and a number of coal companies. This report, which is one in a series, by counties, describes the preparation characteristics of the coals of Harlan County, Ky. From these data it is possible to determine: (a) Which coals, either as mined or after beneficiation by conventional preparation, are chemically suitable under present standards for producing metallurgical coke, (b) Which coals require special and more intensive treatment in preparation than is now practiced; and (c) Which coals cannot be considered to be potential sources of metallurgical fuel regardless of preparation.

Jan 1, 1955

By E. J. Lintner

This paper is one of a series being prepared by the United States Bureau of Mines describing clay mining and crushing methods and costs at various operations throughout the United States. These papers are designed to disseminate technical information regarding methods used. The cost tabulations represent local operating expenditures only and not total production costs. It is recognized that publication of total production costs might perhaps, in many instances, cause embarrassment to the individual operator as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to this distinction in order that no misunderstanding of the scope of the cost tabulation shall ensue. The following report deals specifically with the methods employed by the Camp Brothers Company, Mogadore, Summit County, Ohio.

Jan 1, 1936

By Lester G. Morrell

While developments in Australia dominated the minerals industry of the South Pacific area, New Caledonia's nickel, manganese ore from New Hebrides, gold from Fiji and New Guinea, and phosphate rock from several small islands were significant in world supplies of those materials. The total value of mineral commodities produced in this area in 1965 has been estimated at about $763 million an increase of nearly 16 percent over the value reported in 1964. Increases were recorded in mineral production value with respect to that of 1964 for all of the countries except Papua-New Guinea where lower gold output resulted in a drop of about $300,000 and in the several phosphate-producing islands that collectively recorded a value decline of around $1.3 million. Exploration and development activities continued at an intensified level, not only in Australia and New Zealand but also in the British Solomons, Bougainville, and Fiji. Substantial additions to world supplies of iron ore and bauxite are assured and recent discoveries of natural gas, manganese ore, and nickel combine to give Australia a brilliant mineral outlook. Important discoveries of copper on Bougainville Island and on Vanua Levu, the north island of the Fiji group, and a gold mine on Misma Island were being developed during the year, with plans for early production underway. In New Zealand progress has been made on the New Zealand Steel Company project, and preliminary appraisal of a new titano-magnetite beach sand resource on the South Island has aroused considerable industrial interest. Extensive geophysical investigations were carried out in the British Solomon Islands and on Fiji's goldfields. The expansion program that will double output of products by New Caledonia's Société Le Nickel continued through 1965, and several foreign private companies have expressed a desire to initiate additional industries based on nickel prospects in New Caledonia.

Jan 1, 1967

Work on this program was supervised by R. C. Streeter, Project Scientist, R. K. Young, Principal Investigator, and R. A Glenn, Project Director Technicians involved in the conduct of the experimental work were J R. Allender, D. R. Wolber, G. L Maclay, and A. C Rupert The assistance of Project Scientists C. T. Ford in the electrokinetic studies, and R. R. Care in the spectrographic analyses, is also acknowl- edged. The valued advice and guidance during the course of this program from R. D Hill, EPA Project Officer, and Dr. D R. Maneval, Director of Planning and Coal Research for the Department of Environmental Resources, Commonwealth of Pennsylvania, is sincerely appreciated.

Jan 1, 1971

By E. S. Shedd

Misch metal was electrowon from a treated bastnasite concentrate in a REF3-LiF-BaF2 electrolyte at 950° C. The metal was prepared and tapped from a 1,000-ampere cell, and nearly 100-percent utilization of the rare-earth oxide was achieved. Prolonged operation in a smaller cell (40 amperes) indicated that the composition of the misch metal product was reasonably constant, and no significant increase of impurities, with the exception of carbon, was noted.

Jan 1, 1970

By K. C. Dean

Fine-sized mineral wastes discarded by ore milling plants require stabilization to prevent air and water pollution. Stabilization has been attained by physical, chemical, vegetative, and combination procedures. Vegetative reclamation is preferred to physical and chemical stabilization but is diffi¬cult to achieve because the wastes are sterile, contain deleterious inorganic salts, and lack the essential nutrients and physical characteristics required for sustaining vegetative growth. Methods now have been developed for attain¬ing vegetative growth on all but excessively acidic, basic, or saline tailings at costs ranging from $120 to $650 per acre. The cost for stabilizing tail¬ings requiring more intensive treatment techniques may range upward to $1,750 per acre. This report summarizes procedures developed by the Bureau of Mines and industry for vegetating amenable tailings, lists costs for the various processes, and suggests procedures that may be applicable for stabilizing saline and pyrite-containing tailings. Ridged planting beds, drip irrigation, and deep-furrow planting techniques are suggested for stabilizing saline wastes. A combination of mill tailings and sewage sludge can be used for pro¬ducing synthetic soils, and layers of sewage sludge buried under a layer of tailings offer promise of inhibiting acid formation from oxidation of sulfides in mineral wastes.

Jan 1, 1974

By E. Morrice

The Bureau of Mines investigated methods for beneficiating platinum-palladium ores from the Stillwater Complex, Montana. Results of bench-scale and pilot-scale studies employing froth flotation to recover sulfide concentrates containing platinum-palladium values from a serpentinized ore are presented. Best results in the pilot mill were obtained with a sodium isobutyl xanthate-normal dodecyl mercaptan col-lector combination at a natural pH of 8.2. A rougher concentrate con-taining 1.7 oz/ton Pt and 4.7 oz/ton Pd was prepared. Recoveries of platinum and palladium were 96 pet and 86 pet, respectively. Batch cleaner flotation of rougher concentrates yielded concentrates contain-ing 3.7 oz/ton Pt and 9.8 oz/ton Pd.

Jan 1, 1984

By R. V. Higgins

This paper describes a method and a computer program for calculating shape factors and areas of channels that turn more than 90° and conduct fluids into the backs of wells. The program represents an improvement over a previous Bureau of Mines investigation by using a 4-point Lagrange interpolation equation instead of a 3-point and by summing areas of trapezoids with either x altitudes or y altitudes. Some of the techniques reported in this paper can also be used to compute the areas between contours and the lengths of lines that turn more than 90°.

Jan 1, 1968

By A. U. Miller

Protection against fire is a greater problem at a coal mine, than at an ordinary industrial plant. Generally mines are located in isolated districts and do not have the protection of city fire departments; consequently fire fighting aquipment must be installed by the mining company. Fire protection around a mine is just as essential as it is in the city.. and undoubtedly is more important if the fire should be underground where many lives would be endangered and all means of escape cut off. A surface fire can generally be attacked from any angle, but an underground fire can be attacked only as conditions will permit.. U. S. Bureau of Mines engineers have investigated many serious mine fires that undoubtedly could have been extinguished in incipiency if a fire extinguisher or fire hose and water had been readily available. In past years very little attention was given..to fire fighting equipment and organization around mines, but in recent years three gen a derde hange of opinion among many of those engaged in mining, and nearly all up-to-date mining companies now have some kind of fire protection about their mine Probably the first company in Illinois to install regular fire fighting equipment and effect a fire fighting organization at its mines, was the Madison Coal Corporation, which operates several mines in Illinois. The main office of this company is in Chicago and the general field office is at Glen Carbon, Ill.

Jul 1, 1930

By Martin H. Stanczyk

The Bureau of Mines studied continuous closed-circuit attrition grinding of a coarse commercial filler-grade kaolin to produce paper-coating-grade clay having a particle size analysis of at least 70 percent minus 2-micron equivalent spherical diameter (esd). The coarse clay, containing about 12 percent minus 2-micron-esd material, was ground in a Bureau-developed 10-inch-diameter attrition grinder in closed circuit with a 5-foot-diameter bowl classifier. In the best test, a finished product containing 82.7 percent minus 2-micron-esd material was obtained when grinding 20 pounds of raw clay per hour at percent solids with a 100-percent circulating load. Energy consumption was about 341 kilowatt-hours per ton of clay feed, or 487 kilowatt-hours per ton of minus 2-micron-esd material produced. Closed-circuit grinding gave some-what greater particle size reduction and lower energy consumption than either batch or continuous open-circuit grinding.

Jan 1, 1965

By W. E. Robinson

A laboratory study wan made to determine whether drying and preheating Colorado oil shale with waste retort gases has any appreciable effect on its oil yield. Samples of crushed oil shale were heated at subretorting temperatures in a specially constructed electric furnace by gases similar in composition to waste gases from oil-shale retorts. The results of this study showed that preheating oil shale with nitrogen or a reducing mixture had no effect upon the oil or water yield. However, oxygen in the preheating gas caused a decrease of oil and an increase of water. In general, the oil yield decreased with (1) increase in oxygen content of the heating gases, (2) increase in temperature of the heating gas, (3) increase in heating time, and (4) decrease in the particle size of tho shale. The decrease in oil and the increase in water resulting from preheating were due to oxidation of the benzene-insoluble organic material (kerogen) rather than to oxidation of the benzene-soluble organic material (natural bitumen) in the shale, A small amount of oil was volatilized during preheating, which would constitute an additional loss if prober precautions were not taken to recover it. The results obtained in this laboratory study indicate that oil shale can be preheated without appreciable decrease in oil yield by proper selection of preheating conditions.

Jan 1, 1951

With a growing concern over mine fires, prevention and suppression are hot topics. NIOSH researchers Michael Trevits, Alex Smith and Edward Thimons discuss their research in the area. The leading causes of US mine fires include flame cutting and, welding operations, frictional heating and ignitions, electrical shorts, mobile equipment malfunctions and spontaneous combustion. From 1990 through 2007, there were 1601 reportable fires that occurred in the US mining industry -an average of 89 fires per year. The fact that mine fires are occurring with alarming regularity reinforces the importance of recognizing and eliminating the potential hazards. These statistics also show the need for improved control and suppression technology to ensure worker health and safety if a mine fire does occur.

Jan 1, 2008

By Joel M. Modd, Stephen P. Holt

"INTRODUCTION Nickel is one of the seven metals designated as strategic by the Army and Navy Munitions Board in 1939, when Congress appropriated funds for the investigation of domestic sources of supply of war minerals. The Mertic nickel lode at Punter Bay, Admiralty Island, Alaska, owned by the Admiralty Alaska Gold Mining Co., was investigated as part of this program.During the period 1919 to 1928, the property was examined the following engineers; L. S. Robe, W. E. Dunkic and S.E. Conbest of the Alaska Treadwell Cr., A, F. Buddington of the Federal Geological Survey, and H. C. Boydell. Henry M. Eakin, in the capacity of consulting geologist, examined the deposit in 1928 and later reviewed data resulting; from exploration recommended by him. In 1936, A. Hoogbom, of the Geological Survey of Sweden, made a very brief report on the deposit based upon information furnished by J. S. Pokovich.A comprehensive study by the Geological Survey of the Punter Bay area, including the Mertic lode, was made during the field season of 1937, with brief examinations in 1936 and 1938. 4/Miyaki, representing the Mitsubishi Company, visited the property in 1937 and in the course of his examination took six samples. G. W. Powel examined the deposit in 1937 and took five samples in the Mertie adit.This report describes the results of the Bureau's work and gives information collected from other sources."

Nov 1, 1946

By G. E. McElroy

Changes in existing airway and fan-installation conditions offer the most common opportunities for effecting economical operation of mine ventilating systems, but the largest possibilities for securing this result lie in the original design of the main airways for efficient service. Formulas, and. charts for their graphical solution, are presented herewith for the determination of the elements of airways design when the conditions of service are known, or may be roughly approximated. Although the analyses are made with particular reference to metal-mine airways, there is no essential difference between metal and coal mine main airways, and the methods presented are equally applicable to both. Little attention is paid to designing airways for maximum economy in the ventilation of metal mines. Most of the openings used as main airways are originally designed and used for transportation and other operating purposes. Even where openings are made primarily for ventilation, the possibility of their future use for other operating purposes, or even custom alone, usually results in the selection of a size and shape similar to those of existing openings. Natural conditions, such as heavy ground, often seriously limit the size of opening that can be maintained without excessive expense; and various operating factors, such as velocity limitations on traveling roads, often dictate size requirements in excess of those required for economy in ventilation only. In metal mines the main airways are, as a rule, too small rather than too large for economic service, with the general result that the quantities in circulation are often less than the mine's proper requirements over long periods, even though excessive amounts of power are applied in an effort to remedy conditions.

Jan 1, 1932

By N. L. Wimmler

The Metaline mining district was examined in 1942 by Bureau of Mines engineers with the cooperation of geologists of the Federal Geological Survey. Because the demands of war production were rapidly depleting reserves in some of the older zinc-lead producing districts of the United States, it was decided that an attempt should be made to increase the proved or indicated ore reserves of the Metaline district. With this objective, certain areas to be explored by diamond drilling were selected. The Bureau of Mines began work on this program. January 15, 1943; work terminated September 8, 1945. Forty-five holes were drilled in seven areas, The holes ranged from 154 feet to 2,050 feet in length. Their combined length was 38,150 feet. Thirty-three of the holes were drilled in. the North Pend Oreille and the West Bella May areas.

Jan 1, 1949

By Foster Fraas

This report describes the application of pulsed magnetic fields derived from alternating and intermittent magnetizing currents. Application of such pulsed magnetic fields to the matrix-type separator permits (1) the complete discharge of the magnetic fraction with wet feeds and (2) the dry separation at particle sizes down to 325 mesh. At smaller particle s indications are that frequencies above 60 hertz will be required. Applications of intermittent magnetizing current to the cross-belt separator give the cross-belt-separator an advantage over the conventional constant-field cross-belt and induced roll separators; the intermittent current enables the cross-belt separator to separate matted fibrous and magnetically coagulating feeds, a type of feed that occasionally occurs with mineral, industrial, and secondary materials.

Jan 1, 1973

By B. R. Mohal, S. Chander

"The adsorption and wetting behavior of freshly ground and aged coals has been determined in the presence of a nonionic surfactant. The amount of surfactant adsorption changes with the concentration and ""age"" of the coal. The freshly ground coal has smaller amounts of adsorption at lower surfactant concentrations than the ""aged"" coal whereas at large surfactant concentrations, the order is reversed . In the latter case, more surfactant is adsorbed on fresh coal than on the ""aged"" coal . . It is proposed that at low concentrations, the surfactant adsorbs through both hydrophobic and hydrophilic interactions with the molecule lying parallel to the· surface, whereas at higher concentrations surface micelles form at the hydrophobic sites. The wetting behavior correlates well with the adsorption behavior.INTRODUCTIONNonionic surfactants have many applications in the coal and mineral processing industry. They can be used as dispersing agents to modulate flotation, flocculation and filtration of particulates (1). They can also be used to increase the wettability of hydrophobic solids such as coal and can hence be used as dust suppressants (2,3). Although the adsorption of representative nonionic surfactants such as Triton N-101 (an ethoxylated nonylphenol with 9.5 moles of ~thylene oxide and HLB equal to 13.4) have been studied extensively on substrates such as calcium carbonate (4), silica (5) carbon black (6) and graphite (7), very few studies are available for coals. Coals differ from other substrates with respect to two important characteristics: 1) coal are porous and 2) coals consist of a patchwork of hydrophobic and hydrophilic sites (8). Since the adsorption characteristics of a surfactant are influenced significantly by the nature of the substrate the characteristics of the coals must be taken into consideration."

Jan 1, 1989

By W. A. Selvig

"The purpose of the investigation described herein was to determine how closely different laboratories can check one another in making determinations of fusibility of coal ash with the De Graaf electric coal-ash fusion furnace: how well duplicate determinations by the same laboratory will check, and how the results with the De Graaf furnace compare with those of the standard gas-furnace method of the American Society for Testing Materials.4Thanks are due the following laboratories who cooperated in this study by making fusibility tests with the Do Graaf electric coal-ash fusion apparatus: J. J. Brennan, testing engineer, Northern States Power Co.; R. E. Gilmore, superintendent, Fuel Research Laboratories, Canadian Department of Mines A. T. Leavitt, president, and W. Mueller, chief chemist, Hamilton By-product Coke Ovens. Ltd.; Edgar Stansfield, chief chemical engineer, Scientific and Industrial Research Council of Alberta. Canada; and H. S. Vassar, laboratory engineer, Public Service Electric and Gas Co.The ash-fusibility determinations by the standard gas-furnace method were made in the Coal Analysis Laboratory of the Bureau of Mines at Pittsburgh under the direction of H. M. Cooper, associate chemist. The investigation was made at the suggestion of A. C. Fieldner, chief engineer, Experiment Stations Division of the Bureau of Mines.Routine determinations of the fusibility of coal ash are made in the laboratories of the United States Bureau of Mines by the gas-furnace method. This method was standardized after considerable experimentation5 on the nature of the fusion of coal ash and the various factors which affect its determination. The method was subsequently adopted by the American Society for Testing Materials as one of its standard tests."

Jun 1, 1930