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By J. Gurland

THE microstructure of sintered carbides consists of particles of metal carbides, such as WC and TiC, embedded in a metallic binder which is usually a cobalt—or nickel-rich solid solution. One of the important factors influencing the strength of the alloys is the degree of dispersion of the carbide particles in the binder matrix. While it is generally accepted

Jan 1, 1960

By Lloyd Williams

A vertical air shaft in the Birmingham, Ala., iron district was sunk with a circular cross section and lined with concrete at a relatively low cost to provide needed ventilation for an iron-ore mine. The method of sinking the shaft is described, and the costs are stated in mar-hours with a descriptive list of equipment and a statement on the size and use of temporary buildings. Preparation began May 2, 1955, and the shaft was completed at a depth of [680] feet by September 22, 1956. By October 1956, all temporary building and [aft]-sinking equipment had been removed. The total direct-labor cost for the operation, including preparation and dismantling, was 50,700 man-hours, or 30.2 man-hours per foot. Total rock and dirt removed amounted to 17,523 cubic yards (in place), and the shaft lining required 4,635 cubic yards of concrete to form a circular air shaft with an inside diameter of 16 feet.

Jan 1, 1960

By E. C. Tarpley

The Federal Bureau of Mines has studied solvent extraction as a means of concentrating the mineral components in coal. Solubilities of a number of American coals were determined using abietic acid as a solvent. The effect of rank on solubility was investigated, and maximum solubility was found with coals of intermediate rank. Vitrinite is the most soluble petrographic component; fusinite, micrinitc, and exinite are nearly insoluble. Spore exines also have a low solubility. Abietic acid is a hydrogen donor and reduces pyrite to ferrous sulfide. Mild hydrogenation of high-molecular-weight fragments of the coal structure to those of lower molecular-weight probably contributes to the solvent action. Even where solubility of the coal substance exceeds 90 percent, contamination of the mineral matter with coal makes identification of the mineral components difficult. Further separation might be possible by the application of float and sink techniques to the residue. INTRODUCTION Work n the solvent extraction of coal is conducted to recover commercially useful products and to characterize coal;. and obtain information on their structure. Some coals, particularly those of low rank, contain waxes, resins, and humic acids which can be removed by solvent extraction and find varied industrial uses. In World War II, solvent extraction of coal was conducted on a commercial scale in Germany to obtain a low-ash feed material for hydrogenation and to produce electrodes carbon for the aluminum industry.4 5/

Jan 1, 1960

By H. L. Gibbs

Many factors contributed to the decision to build a radiochemical laboratory at the Salt Lake City Metallurgy Research Center to investigate the application of radioactive isotopes and chemical compounds in extractive metallurgy. These reasons included the notable success achieved in biological sciences with radioisotopes, the development of reliable instruments and methods for identifying the isotopes and measuring their activities, and the commercial availability of radioisotopes in a variety of forms and known activities. The paramount reason, however, was the realization that better methods were needed for guiding and quantifying research to resolve the complex extractive metallurgy problems under study at the Research Center. This is the first of a series of reports describing the application of radioisotopes and radioactivity techniques in extractive metallurgy. The report includes a discussion of licensing and safety requirements, a general description of the laboratory and the methods used, a definition of the nature and scope of the research program, and a synopsis of the more important problems studied. Subsequent reports will concern radioactive techniques for solving specific problems in mineral dressing, hydrometallurgy, and pyrometallurgy.

Jan 1, 1960

By J. B. Gayle

The rate of oxidation of coals with nitric acid has been used by earlier investigators4 5 6/ for determining fusain and for studying petrographic composition. These workers accumulated considerable evidence indicating that, for coals ranging from lignite to low-volatile in rank, the method gives values for fusain that agree satisfactorily with those obtained by optical methods. One group5/even concluded that, when discrepancies are noted between results obtained by chemical and microscopic methods, the results based on the oxidation reaction are probably the more reliable. Unfortunately, after concluding that the method was valid, most of these workers apparently lost interest. As a result, no attempt to exploit or apply the method to problems of utilization has been reported. Recent studies of the influence of inert petrographic constituents on the properties of cokes made from various coals7/ have indicated a need for additional means of characterizing coals and blends used for carbonization.

Jan 1, 1960

By R. F. Tenney

This report has been prepared because little detailed information has been published on the production and use of anthracite producer gas for industrial-process and brick-kiln heating. To obtain this information, an investigation was conducted by the Federal Bureau of Mines in cooperation with a building-brick manufacturer (firing both periodic and tunnel kilns with anthracite producer gas) and with a manufacturer of anthracite-gas producers. In addition to a study of available plant records, 2 weeks was spent in systematic observation and measurement during regular operation of the Hazleton Brick Co. plant, Hazleton, Pa., in July 1953. This report presents the results of this investigation and a description of producer and periodic-kiln equipment, operating procedures, and labor requirements. A summary of the conditions of producer and kiln operation is given for the 2-week observation and for the 11 preceding months. The two 10-foot standard anthracite-gas producers consumed 301 tons of Rice and Buckwheat No. 1 anthracite, as delivered, averaging over 13,000 B.t.u. per dry pound during the 2-week period, with a producer hot-gas efficiency of 95 percent, at an average gas offtake temperature of 5400 F. The yield of gas5/ of 153 gross B.t.u. per cubic foot amounted to 140,000 cubic feet per ton of fuel as fired, or 73,500 cubic feet per kiln heating hour, which was sufficient for kiln requirements.

Jan 1, 1960

By R. K. Young

Producing a sound plant design for a major project requires hundreds of engineers and many drawings. Economical accomplishment of this task is based upon careful and orderly organization of the design team so that at all times there is a complete and workable staff but at no time a surplus of costly talent. This paper will describe the various stages in the development of plant design which normally follow the laboratory and pilot plant investigations discussed in other papers today. An outline of the procedures used in the assembling of a project design group, within an established engineering organization will be presented. Actual procedures may vary according to the size and character of the plant, the special requirements of the owner, and the make-up of the engineering organization performing the design, but most of the points covered will be found to be basic to any plant design project.

Jan 1, 1960

By M. C. Chang, J. Dasher

The Crucible mine in Pennsylvania, operating on Pittsburgh seam coal, is rated at 5000 tpd. The washing plant, built in 1943, is rated at about 400 tph, using hydroseparator boxes to wash the coarse coal (4 x 5/16 in.) and hydrotator units for the fine coal (5/16 x 0). It is generally acknowledged that gravity concentration equipment cannot be used efficiently to bene-ficiate coal finer than about 65 mesh. Before the present flotation circuit was installed, Crucible recovered its fine coal slurry, predominantly —24 mesh material, by passing it through a battery of five 14-in. and one hundred and ten 3-in. Hey1 & Patterson cyclones in parallel with a 75-ft Dorr thickener. About two thirds went to the cyclones and one third to the thickener. Underflows from cyclones and thickener were filtered, respectively, in one 12-disk Eimco and two 4-disk Oliver filters fitted with stainless steel cloth. The resulting cakes were added to the coarse metallurgical coal. The filtrates, overflow from the 3-in. cyclones, and thickener overflow were recycled to the coarse coal plant. The three major problems encountered in this system became acute when the mine switched from track-mounted machinery to the more economical off-track equipment. The quality and uniformity of product declined, too much slime accumulated in the circuit, and waste pond disposal became highly impracticable. Lowering of Quality and Uniformity: Since the filter cake was not beneficiated in any way, addition of this material, which contained about 18 pct ash. would certainly lower the quality of metallurgical coal. Difficulties of handling the high-ash, high-moisture cake were compounded by the lack of adequate blending facilities at the mine, making it impossible to maintain uniform feed for the coke ovens. For a two-month test period, to verify the source of trouble, all filter cake was excluded from the metallurgical coal. The excluded filter cake was stocked in the yard. Slime Buildup: The moisture retained in the coarse coal products and the filter cake provided daily the only means of slime bleed from the circuit. As this bleed was not enough to offset the incoming fines in the raw coal feed, there was excessive buildup of slimes. To operate at all, it was necessary to purge the system each weekend by pumping all the solids from the thickener to a waste pond. The slimes built up during the week progressively increased the apparent viscosity and density of the circulating plant water, so that hydroseparators and hydrotator units had to be constantly adjusted. Uniformity, yield, and quality of the metallurgical coal suffered in consequence, and the filter cake ash and moisture contents increased from Monday to Friday. Limited Waste Disposal: Location of the plant does not permit unlimited waste pond area. Maintenance of a waste pond for the purpose of emptying the thickener during weekends became a costly burden that could not be tolerated. HOW THE PROBLEMS WERE SOLVED The flowsheet (Fig. 1) chosen to overcome these difficulties is considered the one most economical to install and operate. In a preliminary change made before the flotation circuit was installed, the cyclones and thickener were first operated in series, the overflow from the 3-in. cyclones, after flocculation, being discharged into the thickener and the thick-

Jan 1, 1960

By Gill Montgomery

This report covers operations at the Crystal-Victory and Minerva No. 1 mines in Hardin County, Ill., which are operated by the Minerva Oil Co., Fluorspar Division, with offices in Eldorado. It describes the exploration, development, and mining practices, giving costs of each. Transportation, equipment, power, labor, and other influencing factors also are discussed. The mining methods employed are those most applicable to the flat-bedded replacement deposits common to the Cave-in-Rock section of the Southern Illinois fluorspar district. The fluorspar beds occur from surface exposures to 1,000 feet deep. In this district churn drilling is the method practiced for exploring flat-bedded deposits from the surface. Aerial photography and geochemical methods for indicating mineralization have been helpful in planning a drilling program. A program usually includes enough drilling to obtain only sufficient data on the value of the ore body and its structure to justify initial development and purchase of the mineral rights under option.

Jan 1, 1960

By Raphael G. Kazmann

Water occupies a dual role in our industrial society. It is the indispensable raw material, essential to life itself. It is equally an industrial nuisance, interfering with the production of industrial minerals, making construction difficult, flooding valuable land, and generally producing problems because it is in the wrong place at the critical time. The legal position of water as a nuisance, and the counter measures to be taken, have been well established procedures for determining the responsibility for damage caused by water, and the organization of drainage districts and flood control and levee districts have been legally tested many times. Thus there is rather adequate legal doctrine concerning water, the common enemy. But recently efforts have been made to regularize the position of water as a useful, industrial, commodity. Such laws are not new to the West, where the doctrine of appropriation for beneficial use is slowly becoming the water law. Elsewhere the University of Michigan has produced a "model" water law and efforts are being made to induce all of the states to use this law, or a slight variation of it, as the basis for legislation. There are many serious criticisms of the proposed "model"-law, and the writer strongly opposes many of the provisions. But the fact remains that water is, in itself, so useful and essential that laws have been, and will be, passed to insure the orderly development of our water resources and to prevent waste. The, most important aspect of these "water-use" laws is that, wise or unwise, the existing laws and the proposed laws have been "water oriented". "Water oriented" means that it has been tacitly assumed that the beneficial use of water, either surface water or ground water, is the overriding consideration.

Jan 1, 1960

By L. G. Schulz, P. Spiegler

The electrical resistivity and the temperature coefficient of resistivity were measured with a potentiometric method using pure mercury as a reference material. Measurements were made nea,v roorn temperature. A detailed study was made of Hg,TI, near its melting temperature. THE work to be described was originally undertaken to provide the necessary data for interpreting the results of some optical experiments,' but because of the growing importance of liquid metals,273 it appeared that the results of the resistivity measurements should be published separately. For convenience the alloys selected were those which are liquid at room temperature. Special consideration was given to the Hg-T1 alloy closely corresponding to Hg,Tl, because recent X-ray diffraction results of Smallman and Frost seemed to show that the solid structure may persist to some extent into the 1iquid. EXPERIMENTAL PROCEDURE A potentiometric method was employed in which the resistivity of mercury was used as a reference. The essential features of the samples are shown in Fig. 1. A capillary tube CT with a bore of approximately 1.5 mm was fitted into two end cups, T, which were made of Teflon. A pair of current electrodes CE were immersed into the excess liquid metal which partly filled the end cups. The potential electrodes PE were inserted into CT through short pieces N of a no. 18 hypodermic needle held in place with Saureisen cement SC. As shown, the lower ends of the PE7s were reduced in diameter to 0.25 mm to minimize the distortion of the liquid metal cross section. Several methods were used to insert an alloy into the sample, but the usual one with mercury alloys was to fill the sample container with a weighed quantity of pure mercury* and then add weighed the sample tube in a vacuum. Because of rapid corrosion, samples containing gallium were of necessity prepared in a vacuum. To obtain the specific resistivity of an alloy the resistance of the sample containing the alloy was measured and compared with the resistance when the container was filled with mercury. Resistances were measured in the temperature range of 20" to 60°C to obtain the temperature coefficient of resistance. The electrical measurements were made by connecting the sample in series with the standard one-ohm resistance, and the potential drop measured alternately over the sample and the standard resistance. To correct for stray thermoelectric effects provision was made for reversing the direction of the current, and the true potential drop was taken to be the average of that obtained for the two directions of current flow. Various materials were used for the electrodes, the most uniform results being obtained with nickel. EXPERIMENTAL RESULTS The numerical results are presented graphically in Figs. 2 and 3 and in tabular form in Tables I and 11. Following are remarks on results of individual alloys. 1) Hg-In—This was the first alloy studied, and

Jan 1, 1960

By W. A. Grosh

Records show that much of the lead produced in the Upper Mississippi Valley lead-zinc field was taken from natural openings along crevice systems at shallow horizons or at the surface. During the early history of the district, the shallow deposits were worked intensively; but in recent years the production of lead, except as a byproduct of deeper mining for zinc ores, has not been significant. Considering the methods of early mining, the character of mineralization, and the fact that galena can still be found on the surface of the old digging areas, it was reasoned that enough mineralization might remain on and above bedrock to permit, through the use of modern equipment and methods, economical re-treatment of surface material in the digging areas.

Jan 1, 1960

By G. Bridgstock, S. S. Forbes, E. M. Elkin

"OPERATIONS at Canadian Cop-per Refiners Limited, since the refinery was established in 1931, have been described in previous papers ( 1,2). Since then the refinery has treated the entire copper output of Noranda Mines Limited and Hudson Bay Mining & Smelting Company Limited. With the commencement of production in 1956 at Gaspe Copper Mines Limited, this copper has also been refined. From the start of operations to the end of 1958, the following had been refined: copper, silver, gold, selenium and tellurium.Construction of new buildings and additions to other buildings have been needed to handle increased receipts. The refining capacity has been increased from 112,000 tons of copper per year to a total of 236,000 tons per year.The refinery is located at Mont-real East, Quebec, close to railway and highway facilities. Incoming materials and shipments, with some small exceptions, are handled by rail. Some finished products are sl1ipped by industrial flatcar to the adjoining plants of Canada Wire & Cable Company Limited and Noranda Copper & Brass Limited."

Jan 1, 1960

By R. F. Tenney

The performances of four anthracite-burning stokers have been observed under identical 74-hp. steam boilers. Fifty runs of 12 and 24 hours' duration were made in accordance with the test code of the American Society of Mechanical Engineers (ASME). The capacity of each stoker for burning anthracite has been determined, the heat efficiency at each fuel rate has been computed, and the various significant items of hear loss have been estimated. The operating data and results from each run are tabulated in this report in the form used in the test code. The heat efficiencies and most significant operating data for each run are also presented graphically for each stoker to establish the trends with increasing boiler outputs, The tests show that rice anthracite can be burned on stokers adapted to its use at heat-conversion efficiencies of 82 percent or more under continuous firing. These high efficiencies are maintained with fuel inputs 30 percent higher and lower than the peak efficiency rate. Moreover, a heat efficiency of 70 percent or more is obtained at 50 percent of the optimum fuel rate, even though the excess air into the furnace cannot be held below 150 percent.

Jan 1, 1960

By Robert E. Hershey

The phosphate industry is the fourth-ranking mineral industry in Tennessee; it has an annual value of 13,000,000 and a yearly production of almost 2,000,000 tons of phosphate ore. Tennessee, at present, is second in rank of phosphate production in the United States. In accord with the importance of this mineral commodity, the Tennessee Division of Geology, is conducting a continuing study of the industry' and the raw s, materials upon which it is dependent. Of the three type's of phosphate found in Tennessee, the brown phosphate rock of the Bigby faces of the Bigby-Cannon limestone is by far the most extensive in occurrence and is the only type being mined at the present time. Because of the importance of the brown phosphate ores, our Division has mapped , in detail the outcrop pattern of the Bigby facies of the Bigby-Cannon limestone. The geologic mapping was done by Dr C. W. Wilson, Jr. and others under his super-vision and the geology plotted on 7 1/2-minute topographic maps, with scale of 1 to 24,000 or 1 inch equals 2,000 feet. These maps will be available for use in the near future and will be published later-with complete geologic coverage.

Jan 1, 1960

By R. M. Lauer

OVER THE YEARS concentration of the Sullivan ore has become progressively more difficult as the ore has become increasingly refractory. The introduction of new reagents and changes in the flow of the concentrator have been and continue to be necessary in order to maintain and improve the efficiency of metal extraction. Prior to the completion of the pilot mill in 1957 ail new ideas were developed in laboratory equipment. If these were found to be promising, there was no alternative but to introduce them directly to the main mill flow in one step. When a major change was involved there was always the possibility of serious losses while the mill was being adjusted to the changed conditions. It proved difficult to determine whether these losses were the result of the changed procedure or of failure to adjust the flow to a change in the condition of the ore during the test. The pilot mill has provided a valuable intermediate step between the laboratory and the mill. It avoids the losses which occurred when unsuccessful full-scale tests were attempted, and conversely it provides assurance that full-scale flow changes can be made without serious hazard.

Jan 1, 1960

By David J. Kusler

This report describes a rapid, reliable, and relatively simple method developed by the Bureau of Mines Pyrometallurgy Laboratory at Bruceton, Pa., for determining lime (calcium oxide) and magnesia (magnesium oxide) in various materials containing these constituents in greater than trace amounts. Optionally, titania (titanium dioxide) may be determined for the same sample. The accuracy of the method, suitable for most purposes, is shown by comparing the Bureau results with those obtained by accepted procedures. The method has been applied satisfactorily to the routine analysis of blast-furnace slags, for which purpose it was primarily developed, and to other calcareous compositions. In the Pyrometallurgy Laboratory it has replaced the standard methods previously used to determine lime and magnesia, and has been in general use by that laboratory for the past several years. The analysis time, generally under 3 hours, is considerably less than required by standard methods.

Jan 1, 1960

By H. Marshall Farrier

In the past few years the world petroleum industry has increasingly felt the weight of changes in the principal economic factors affecting pro¬fits. As a result of, these changes, it has been necessary for many oil companies to acquire certain new facilities in order to strengthen their competitive positions and thereby protect their tremendous investments in crude oil reserves, pipe line facilities, refining operations, and marketing outlets. Principally these needs have been met by new capital outlays. A supplementary, method of acquiring needed facilities, however, has been to obtain existing facilities through complete or partial acquisition of other companies.' properties. It is this method of meeting competitive pressures with which this paper is concerned. This paper presents a statistical breakdown of the mergers and acquisitions which occurred in the oil industry between January 1, 1954, and October 1, 1959, showing the frequency' with which certain types of properties were acquired in each of the years studied. In addition, it discusses the principal economic conditions which stimulated many of these property trans¬fers, comments on the effects of these mergers on the consuming public, and indicates the types of, mergers and the rate at which they may be expected during the next three or four years. The basic data upon which the statistical analysis presented in this paper is based were taken from several published sources. Obviously they are somewhat incomplete because not all mergers and acquisitions were reported However;, a careful search was conducted through, The Wall Street, Journal, The Oil and Gas Journal, Potroleum Week, and The Oil Daily with the result that the data should be reasonably complete and comparable for each of the years studied, It is believed, therefore, that the statistical analysis which' follows provides a reasonably accurate indication of the general trend in mergers and acquisitions during the period studied.

Jan 1, 1960

By Marvin W. Wilson

The Federal Bureau of Mines has conducted laboratory experiments simulating underground gasification of coal to study the feasibility and mechanism of the process and determine the chemical and physical characteristics of a coal-bed during gasification. Laboratory and small-scale field experiments also were made to investigate the properties of coal and other factors affecting the electrolinking-carbonization method of preparing a path through a coalbed before gasification. Laboratory experiments simulating underground gasification of coal: Experiments with a laboratory retort indicated that bituminous-coal deposits could be gasified in place to produce a combustible gas.

Jan 1, 1960

By Kenneth H. Johnston

For the past several years, Bureau of Mines petroleum engineers have arranged tours of selected waterflooding projects for the spring meetings of the Kansas-Oklahoma Waterflood Association. These tours are conducted to demonstrate unique operating methods and new field equipment and to provide additional opportunities for exchanging information. Each of these tours has been supplemented by a published report describing in detail the projects visited. This report has been prepared for distribution during the 1960 spring tour of four waterflooding projects in Greenwood County, Kans. (fig. 1). Three of the projects produce oil from the Bartlesville sand, and one produces from the Cattleman sand. The Bartlesville-sand floods have been in operation from 4 to 12 years and have produced about 3,910,000 barrels of waterflood oil from the injection of approximately 64,715,000 barrels of water, a cumulative water-injected to oil-produced ratio of 17 to 1. The Cattleman- sand flood, which has been operating for 3-1/2 years, has produced about 842,000 barrels of waterflood oil from the injection of approximately 9,305,000 barrels of water, a cumulative water-injected to oil-produced ratio of 11 to 1.

Jan 1, 1960