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By Wilbur I. Duvall

Surface vibrations of ground, rock, and structures resulting from blasting or other sources are often measured with portable seismographs. These instruments are usually supported by a three-point mount or tripod which is simply placed on a horizontal surface on which vibration levels are to be measured. The rigid-body motion of a tripod-supported seismograph is considered from the point of view that there should be no slippage of the feet with respect to the surface and none of the feet should leave the surface as a result of imparted motion. From these studies the following design criteria are deduced which assure that the seismograph will respond accurately to vibration levels as large as 1/2 g.:3/ First, the coefficient of friction between the feet and the surface on which the instrument rests should be as large as possible, preferably approaching unity; second, the center of gravity of the instrument should be vertically above the centroid of the three-point mount; and third, the vertical distance between the center of gravity of the instrument and the centroid of the three points of contact with the surface should be less than the perpendicular distance between the centroid point and anyone of the three sides of the triangle formed by the three points of contact. Portable seismographs that do not satisfy these conditions should be clamped to the surface if vibration levels above 0.1 g. are to be recorded.

Jan 1, 1961

By W. R. Huff

This report describes the development and operation by the Bureau of Mines of a pilot plant designed for using high-volatile A bituminous coal-in-water suspensions as a source of preheated coal and superheated steam in the pressure gasification of coal with oxygen. Figure 1 on page 2 is a block diagram of the integrated gasification process, in which a total of 70 tons of coal was fed from slurry and gasified. The present work included (1) development of equipment and methods both for mixing pulverized coal and water to produce slurry and for pumping and metering the slurry at gasification pressure; (2) development of equipment for heating the flowing slurry and, because slurry that can be pumped produces more steam than is necessary as a gasification reactant, developing equipment for removing and metering the excess steam; and (3) demonstration of the process under actual gasifier operating conditions, at a coal rate of about 800 pounds per hour and gasification pressures in the range 100 to 300 pounds per square inch gage. By using the forced-convection principle, a flow of slurry made from a caking, high-volatile A bituminous coal can be continuously heated to 600° F. in a coil-type heater. The flow rate and concentration of the slurry and the temperature gradient along the length of the heating coil must be closely controlled. In a radiant-type heater, involuntary reductions in flow rate, even momentary, can lead to coking and plugging of the heater coil.

Jan 1, 1961

By Miles B. Royert

Crude Minnesota taconite was charged in the Bureau of Mines experimental blast furnace so that smelting characteristics of such highly siliceous raw materials could be studied and smelting costs compared with those of a standard Mesabi ore. The Bureau recognized that the highly siliceous nature of the crude ore and its relatively low metallic content would be serious economic deterrents to commercial use of the raw taconite, but compensating factors would be low capital investment in production facilities, large tonnage available on short notice, high recoveries of iron, and low delivered cost. Crude taconite smelted readily in the experimental blast furnace. Coke consumption per ton of metallic product was very high, compared with the average established requirements for smelting normal grades of metalliferous raw materials. Slag rates were also inordinately high. Metal quality was erratic as to silicon, and sulfur contents were objectionably high.

Jan 1, 1961

By G. V. Sullivan

This report summarizes the results of metallurgical investigations by the Federal Bureau of Mines of manganese oxide ore, averaging 23 to 25 percent manganese, stockpiled at the Butte-Philipsburg depot of General Services Administration (GSA). The oxide ores were stockpiled in two general classifications, straight oxide ore and mixed oxide-carbonate ore. Continuous-circuit flotation tests at the Albany (Oreg.) Metallurgy Research Center of the Bureau of Mines showed that each of these ore types could be concentrated by an oil-emulsion scheme to produce a concentrate that could be sintered to meet program specifications. About 88 percent of the manganese was recovered in the concentrate from the straight oxide sample, with the sintered concentrate containing 48 percent Mn. The sintered concentrate from the mixed oxide-carbonate sample contained 41 percent Mn with a recovery in the concentrate of 95 percent.

Jan 1, 1961

By David M. Gullikson

As part of its program of petroleum production research the Federal Bureau of Mines has long been engaged in the study and development of systems of analysis of oilfield waters (8, 12, 20, 21, 22, 27, 30).21 However, many of the early chemical procedures developed by the Bureau and widely adopted by the petroleum industry are time consuming, and some are unreliable for determining certain constituents found in California oilfield waters. Because of the need for more rapid and more accurate methods having greater sensitivity with low concentrations of some constituents, a study has been made by the Bureau's Petroleum Research Laboratory at San Francisco, in developing new techniques and modifying previously published techniques for analyzing oilfield waters by flame spectrophotometric, potentiometric, and colorimetric methods. Test solutions were synthesized for testing the suitability and accuracy of the procedures, and the effect of interfering ions. These solutions contained known quantities of characteristic constituents of oilfield waters including sodium, magnesium, potassium, calcium, lithium, strontium, barium, sulfate, chloride, bromide, iodide, carbonate, bicarbonate and borates in a wide range of concentrations. The compositions of these synthetic brines are listed in table 22. Many California oilfield waters contain salts of petroleum-derived organic acids and several synthetic oilfield waters also were prepared to which large quantities of naphthenates or salts of petroleum acids were added.

Jan 1, 1961

By A. L. Engel

This report is a compilation of preliminary and, in some cases, more extensive concentration experiments by the Federal Bureau of Mines on low-and medium-grade fluorspar ores from three localities in Nevada and one in California. The work was done on samples obtained from Shoshone mine, Nye County, Valery mine, Pershing County, and the Broken Hills mine, Mineral County, all in Nevada, and Dirty Weather mine, Inyo County, Calif. These investigations were made to aid in the development of domestic fluorspar resources, in line with the Bureau's long-established program of conservation of mineral resources. The treatment methods employed in the experimental work described included simulated or "heavy-liquid" gravity concentration of coarse minerals and comparatively fine-grained minerals, and flotation concentration of finely-ground minerals. These methods were attempted in order to beneficiate the ores and produce concentrates which could be marketed readily, with as high a recovery rate as possible, while using simple treatment methods suitable for small-scale operation.

Jan 1, 1961

By W. M. Dressel

The Federal Bureau of Mines has obtained data by differential thermal analysis of the various minerals that represent the nation's resources in manganese. These data are supported by X-ray diffraction analysis, chemical analysis, mineralography, and optical mineralogy, and provide fundamental information on the response of each mineral to thermal treatment in oxidizing, reducing, and neutral atmospheres. The information can be applied advantage¬ously in the identification of manganese minerals. Its greatest potential value, however, lies in the application of the quantitative data on the reaction temperatures, rates, and products to the more efficient extraction of manganese from U.S. ores. Thermal analysis curves are presented for certain manganese minerals, namely hausmannite, bixbyite, braunite, pyrolusite, lithiophorite, cryptomelane, hollandite, manganite, rhodochrosite, and rhodonite. The original minerals and the products of their thermal decomposition were identified by X-ray diffraction analysis, supplemented by chemical analysis and mineralogical identification.

Jan 1, 1961

By E. C. Perkins

The purpose of the research described in this report was to develop techniques for using ilmenite from domestic deposits for the production of titanium tetrachloride. The research was done by the Federal Bureau of Mines in cooperation with the General Services Administration under contract DMP-116, Utilization of Domestic Ilmenite. Bench-scale continuous chlorination of an Idaho ilmenite containing 27.9 percent titanium and 35.6 percent iron yielded a crude titanium tetrachloride suitable for purification and for the production of titanium metal and pigment. A summary of the results of 380 hours of operation showed that 82.4 percent of the titanium was chlorinated, with 92.5 percent utilization of chlorine. The construction- of a. quartz tube chlorinator 4-inches in diameter and 24 inches long is described with the necessary details of operation.

Jan 1, 1961

By Kenneth G. Broadhead

The objective of this rare-earth oxalate study by the Bureau of Mines was to determine systematically by radiochemical techniques what effects, if any, could be attributed to the several variables--temperature, digestion time, acid concentration, rare-earth concentration, oxalic acid concentration, stirring, and the presence of other rare-earth ions. A Latin Square experimental design was used to evaluate statistically some of the variables. Precipitation losses ranged from near zero to about 7 percent, and mineral acid and rare-earth concentration were the predominant factors affecting completeness of precipitation. Quantitative oxalate precipitation of the rare-earth elements was achieved by controlling the experimental conditions as follows: (1) Maintaining rare-earth concentrations above 0.01M; (2) stirring the mixture several minutes after precipitation; (3) using an adequate (two to five-fold) excess of oxalic acid; (4) precipitating at room or iced temperature and digesting for at least 1 hour; (5) avoiding an excess of mineral acid and, if possible, maintaining the pH above 2.0; and (6) avoiding excess complexing agents such as EDTA (ethylenediaminetetraacetic acid). In the past 20 years research aimed at developing more efficient separation and purification techniques applicable to the rare-earth elements and yttrium has been extensive. Common to most of these procedures has been the use of oxalic acid to precipitate this group of elements selectively. However, this particular use of oxalic acid has a much earlier origin; its application in precipitating yttrium was first reported by Mosander (8)4 in 1843. Despite long and popular employment of this technique, only limited and somewhat conflicting data are available regarding the many factors affecting the degree of rare-earth oxalate precipitations.

Jan 1, 1961

By J. T. Dunham

Zirconium has possible use in industry where severe corrosion conditions are encountered because it resists attack from a variety of corrosive environments. However, very little experimental testing has been done to evaluate the corrosion behavior of zirconium when simultaneously subjected to high tensile stresses and exposed to corrosive environments. This investigation was initiated for an evaluation test, but was limited to environments consisting of ferric chloride solutions which were known to attack zirconium and were shown to promote stress-corrosion cracking in preliminary tests. Tests for cracking susceptibility were conducted by the Bureau of Mines to show the effect of stress, solution concentration, air aeration of solution, and the method of mechanical processing. Tensile stress was applied to the specimens by a constant-load method which proved more reliable than a constant-strain method.

Jan 1, 1961

By Alton B. Cook

The practice of using partly depleted oil reservoirs for gas-storage operations is proving successful. Moreover, this practice provides a method of secondary oil recovery when gas is cycled at full-storage reservoir pressure. Because of the relative newness of this operation, a study was undertaken to assist engineers in developing improved gas-injection and production procedures and in calculating the amount of gas needed for completely repressuring reservoirs. This paper is the third in a series reporting the progress of a study by the Federal Bureau of Mines of reservoir performance during complete gas repressuring and gas cycling. A procedure for estimating secondary oil recovery by this method is also under study. One report (7)3/ describes the laboratory equipment. The other report (8) gives (1) data on the New York City field, Clay County, Tex., which has been converted to gas-storage operations; (2) laboratory data from research with a model oil reservoir, in which primary production, complete gas repressuring, and gas cycling for the New York City field were simulated; and (3) theory to explain reservoir performance during gas repressuring.

Jan 1, 1961

By A. L. Engel

This report describes results of laboratory-scale experimental treatment of nine ores containing gold and silver, including samples of products of previous plant treatment, from ore deposits in California and Nevada. The samples treated were taken by engineers of the Bureau of Mines during investigations of these ore deposits. The information reported is of interest for development of the mining districts represented or in future Investigations of similar ores from other sources. The treatment methods were as simple as possible. More complicated treatments were tried when required, The applicability of the methods and their limitations in treating the ores are shown by the data in this report. The following treatment methods were employed in the experiments described: Screen analyses were made to determine distribution of values in various screened-sized portions of crushed ore, or to determine optimum size to which a particular ore should be crushed or ground to liberate values, and some-times to determine residual values in various-sized portions of treated material.

Jan 1, 1961

By T. A. Henrie

One objective of Project Gnome is to study the feasibility of a phase of the Plowshare program recovering thermal energy from an underground nuclear explosion. The test will be conducted in an underground salt deposit. It is anticipated that some of the energy thus released will be stored as thermal energy in molten salt. This report describes the pre-Gnome experiments conducted at the Federal Bureau of Mines Metallurgy Research Laboratory, Boulder City, Nev. The objectives of this study were to determine the problems involved in the recovery of thermal energy from molten salts to assist in planning the experimental program for the Gnome project.

Jan 1, 1961

By Perry D. Teitelbaum

In two earlier studies the Federal Bureau of Mines undertook to explore comprehensively the dimensions of the Nation's energy balance. The first of these studies, published in 1950 as Bureau of Mines Information Circular 7582, by Harold J, Barnett, was primarily concerned with projections of future domestic energy requirements and supplies, because these related to projected growth in major fuel-consuming sectors of the economy, changing rates of energy-use efficiency, and interfuel substitution patterns. But, to provide the essential background for these projections, it was first necessary to assemble and examine in some detail the quantitative information on the size and shape of the current United States fuel economy. Among other things, Barnett's path-breaking study indicated the need to consider energy as an entity, particularly for public and private policy makers, industry and commodity analysts, economists, and others concerned with long range questions of domestic and international energy supply and demand. The study also spotlighted a gap in the fabric of current economic intelligence; no comprehensive collation and reconcilation in any single report of available published statistical information covering the origin -a disposition of all energy materials existed. In response to this latter need, the Bureau of Mines prepared the second of the two studies referred t3 above. This was published in 1951 as Report of Investigations 4805, by W, H, Lyon and D, S. Colby, and it consisted of statistical information on the production and use of each of the various fuels and electric energy in the United States for 1929, 1939, and 1947; all were presented in tabular form and on a uniform basis. The three years selected were chosen largely on the basis of data availability.

Jan 1, 1961

By Lowell Stroud

Since 1929, the Helium Activity of the Bureau of Mines has operated a helium-extraction plant at Amarillo, Tex. The natural gas that supplies this plant is obtained from the Cliffside geologic structure 12 miles to the northwest and over the years, has become known simply as "Cliffside gas," There is need for published data on the low-temperature phase equilibria of helium-bearing natural gases. To date, little information has been published on the equilibrium phase compositions, solution of helium in condensed natural gas, condensation characteristics, or equilibrium vaporization coefficients for methane, nitrogen, and helium in helium-containing systems. A windowed phase equilibrium apparatus (8)6 was used to obtain 105 equilibrium samples, representing 35 experimental conditions of condensed Cliffside gas at pressures of 100, 200, 300, 400, and 500 p.s.i.a. and temperatures from 0° to -270° F. Data on equilibrium vapor-liquid composition for Cliffside gas are presented in both tabular and graphic form and are discussed in detail to show their relationship to certain criteria that must be met to effect an efficient separation of helium from natural gas by means of low-temperature processes. Facts about condensation characteristics and solution of helium in the liquid phases are included, The important relationship of these two factors in decreasing the percentage of total helium lost by solution in the liquid phase is discussed.

Jan 1, 1961

By P. C. Good

Tungsten metal in fused form and of high purity was prepared by reducing tungstic oxide with redistilled calcium metal in a heavy-walled sealed reactor. Alloys of tungsten with vanadium, molybdenum) chromium, columbium, and tantalum were prepared by coreduction of mixed metal oxides in the same manner. This work was undertaken by the Bureau of Mines to investigate new approaches for preparing tungsten and its alloys in high-purity form. The standard method of producing tungsten metal has been the reduction of tungstic oxides by hydrogen. The resulting metal powder is compacted, sintered, and fabricated by powder metallurgy methods. Long experience in this field has resulted in the development of a technology that (by careful control of the variables such as metal composition, particle size, and sinterng technique) is well adapted to producing wire and the small shapes usually prepared from tungsten metal.

Jan 1, 1961

By Scott W. Hazen

In recent years many mining companies have recognized that their chance for continued economic survival depends on the adaptation of technological advances in their operations. Increased productivity through new developments in mining methods and improvements in equipment has made mining and processing of lower grade ores possible. Cost analysis has produced accurate data on the costs for development, production, and processing of ore. All of these changes and cost studies have shown the necessity for increased accuracy in determining the grade of ore. Methods of estimating grade in a mineral deposit have not kept pace with the technological advances in the other areas. The same methods are in use today as in the past. Experience and judgment are major criteria of accuracy and the results are highly subjective. In 1953, as part of its research program to develop a better understanding of fundamentals of mining technology, the Federal Bureau of Mines began a sampling method research project at its Denver Mining Research Center. The basic objective of the project is to investigate sampling methods and to study the adaptation of the techniques of statistical analysis to mine sampling.

Jan 1, 1961

By Charles W. Huggins

Electron diffraction and electron microscopy were used to determine the unit cell parameters of garnierite [(Ni,Mg)3 Si2O5 (OH)4] and to examine its crystal habit. Bundles of ribbons, many less than 200 A. in cross section, make up the bulk specimen of the garnierite Electron diffraction revealed the unit cell to be monoclinic. Unit cell parameters were: a, 5.33 A,; b, 9.23 A.; c, 14.96 A.; and ß, 94°441.

Jan 1, 1961

By K. K. Kershner

Nickel having a purity of more than 99.99 percent with reference to metallic impurities was electrodeposited at the Rolla Metallurgy Research Center of the Federal Bureau of Mines. The production of high-purity nickel is in keeping with the current trend in technologies for producing metals with lower and lower percentages of impurities. To understand more fully the role to be played by nickel by itself and as a component in many alloys, the element must be in a state of high purity. Procedures are outlined for purifying nickel solutions by precipitating and filtering off impurities. Details are given for using the purified solutions as electrolytes in depositing high-purity nickel. The elecneleposited nickel contained 0.0005 to 0.002 percent each of cobalt, copper, aid iron together with spectrographically detectable traces of aluminum, magnesium, and silicon. The deposits were smooth and dense; the crystalline structure was typical of an electrodeposited metal. Some preliminary experiments for purifying nickel solutions by liquid-liquid extraction are also described in this report. Tests of this type were limited since more encouraging results were obtained by other methods of purification.

Jan 1, 1961

By V. T. Dow

In April 1957 the Bureau of Mines instituted a reconnaissance of titanium-and zirconium-bearing heavy sandstone deposits in the Four-State area of Utah, Wyoming, New Mexico, and Colorado. This report summarizes the study. Eighty-two deposits or groups of deposits, containing an estimated 27,920,000 tons of titaniferous sandstone, were examined in the Four-State area; 16 in southern Utah, 19 in Wyoming, 33 in New Mexico, and 14 in southwestern Colorado. The 16 deposits examined in Utah contain an estimated 1,043,000 tons with an average grade of 17.98 percent TiO2, 5.67 percent ZrO2, 20.98 percent Fe, and 0.09 percent equivalent Th02. The 19 deposits investigated in Wyoming are estimated to contain 21,873,000 tons of titaniferous sandstone having a weighted grade of 5.22 percent 702, 0.55 percent ZrO2, 24.8 percent Fe, and 0.01 percent equivalent Th02.

Jan 1, 1961