Search Documents

By W. M. Weigel

Langley is about nine miles north of Augusta, Georgia., on the Sou them :l;.ilv1ay. According to the South Carolina. Geological Survey, tr.e district is known a.s tr. Horse Creek and Town Creek sub-areas of the Aileen or Savannah River Area f the South Ciil.Z'olina Coastal Plains. The geology and origin of the clays 3l"e Jscribea in a bulletin of the South Carolina Geological Survey (Series 4, Bull, l; "A Preliminary Report on Cl.:.ws of South Carolina.-), According to this report, i.he clays are sedimentary kaolins, in the Mid.dendor! and Hamburg series of the Cretaceous Age.

Aug 1, 1922

By R. L. Hopkins

Fifteen alkyl cycloalkyl sulfides and three dicycloalkyl sulfides were synthesized to provide reference compounds in the search for these classes of sulfur compounds in crude oils. In synthesizing sulfides by alkaline alkylation the order in which the reactants were added was shown to determine the yield and purity of the product.

Jan 1, 1966

By Frederick K. Allgaier

This report presents the final data from a 5-yr Bureau of Mines study designed to determine the surface subsidence characteristics resulting from longwall coal mining in a geologic environment common to the Western United States, It includes a description of the geologic setting of the study site, the mine plan, measurement techniques, and results of the monitoring program. Measured subsidence values were obtained over four adjacent longwall panels- Major subsidence characteristics such as longitudinal and transverse profiles, angles of draw, time-related subsidence development, and critical width are discussed. The maxima subsidence value of 5.8 ft was 68 pct of the mining thickness. The average angle of draw was 30°, Subsidence at the center of the first panel continued for 46 months following undermining. The lengths of the longwall panels precluded a definitive determination of the critical width and maximum possible subsidence.

Jan 1, 1988

By O. C. Blade

This report on the properties of motor fuels sold through service stations in the United States was made in accordance with a cooperative agreement between the American Petroleum Institute and the Bureau of Mines of the United States Department of the Interior. This paper i8 a continuation of a series made in cooperation with the Coordinating Fuel Research (CFR) Committee of the Coordinating Research Council (CRC), Inc. The first of this series of reports presented data on motor gasolines sold during the winter of 1935-36, and succeeding reports described motor gasolines Bold during the summers and winters to and including the summer of 1941 Y. No reports were made on motor gasolines sold during the winter of 1941-42 and during the summer of 1942. However, starting with the winter of 1942-43, the semiannual reports were resumed.

Jan 1, 1951

By William Cochran

The mineral waste disposal system at the Grace Mine, Morgantown, Pa., was designed to minimize environmental effects while allowing much of the waste from the iron mine, mill, and concentrator to be utilized. Standard cost estimating procedures were used by the Bureau of Mines to determine waste disposal costs. Mill tailings and rock waste disposal costs were estimated at $0.151 and $0.276 per ton, respectively, for the 1965-67 production period. Total waste disposal cost was reduced about $0.015 per ton by utilizing part of the waste as aggregate. The net average cost for disposal of all mineral waste was $0.189 per ton.

Jan 1, 1969

By D. D. Harbuck

To decrease reliance on foreign sources for the strategic and critical metals gallium and germanium, the U.S. Bureau of Mines identified and developed processing technology for two domestic sources of these metals: a Tennessee zinc residue and a Utah ore. Sulfuric acid (H2S04) solutions were used to solubilize gallium and germanium in both sources. Statistically designed experiments showed that the most important parameter for high metal extraction from zinc residue was the H2S04 concentration. At a concentration of 2.9M H2S04, 95 pct of the gallium was extracted, and at a concentration of 0.6M H2S04, 73 pct of the germanium was extracted. Controlled H2S04 concentration was also the key for high metal extractions (97 pct Ga, 87 pct Ge) from the Utah ore. Such control was achieved using a two-stage countercurrent leach circuit. Testing showed that the insoluble germanium in both the residue and ore was tied up with silica. Several methods for overcoming this problem are given. To recover gallium and germanium from the leach solutions, the solvent extractants octylphenyl acid phosphate (OPAP) (for gallium) and LIX 63-OPAP (for germanium) were identified. These extractants were tested in separate, continuous, solvent-extraction circuits yielding a gallium recovery of 94 pct and a germanium recovery of more than 90 pct.

Jan 1, 2010

By J. D. Ramsdell

The object of this investigation by the Federal Bureau of Mines was to evaluate the workability, recrystallization characteristics, and mechanical and physical properties of high-purity electrorefined vanadium. The low level of interstitially soluble elements in electrorefined vanadium results in a soft ductile metal which responds readily to cold working by rolling, swaging, and press-forging. Hardness, strength, and resistivity increased with an increase in impurity content, but thermal expansion was independent of impurity content. The work-hardening of vanadium occurs rapidly. Most of the hardness increase occurs in the first 15 pct. of reduction in area. When vanadium is annealed, its hardness increases to a maximum when the annealing temperature is between 200° to 400° C. A sharp decrease in hardness develops as the annealing temperature is increased. An anomaly in the hardness versus annealing temperature curve is present in the 600° to 800° C. range, while all evidence of cold-work is removed at annealing temperatures above 900° C.

Jan 1, 1961

By Paul. E. Pesonen

Since early in 1940 the Bureau of Mines has been concerned with possible means of utilizing manganese-bearing materials from the Missouri Valley manganese deposit. During the period between July 1945 and August 1947, the Bureau of Mines undertook to complete certain phases of the problem by re-evaluating the results of earlier work and supplementing the findings by additional operations and field studies considered necessary to permit drawing of final conclusions. Distinctive discoloration marks the outcrop of the manganese deposit which is exposed on both flanks of the Missouri River Valley and its major tributaries for a peripheral distance of approximately 523 miles in south-central South Dakota. The apparent magnitude of the deposit, judged largely from observation of the outcrop, had led to much speculation as to its actual value in terms of tonnage and grade. Similarly, investigative work aimed at developing a means of winning a usable manganese-rich product from the deposit had reached no conclusion, except that certain methods showed more promise than others for accomplishing the final objective.

Jan 1, 1948

By R. E. Morgan, J. F. Barkley

"INTRODUCTION In city smoke-abatement work it is customary to require approval of the sizing of fuel-burning equipment. This is to insure that, with reasonable attention, the equipment can be operated essentially smokelessly, having such features as ample furnace volume and air supply. To answer the many inquiries that come to the Bureau of Mines as to what dimensions are acceptable and standard, the requirements of a number of smoke-abatement ordinances have been tabulated.CONCLUSIONSStudy of these tabulations shows that even after many years of fuel-burning practice and experience there is no common standard. Variations in the requirements for the same type of equipment under the same conditions of operation are great. This causes considerable difference in installation costs. Over-all costs being affected, the competitive positions of different types of fuel-burning equipment are also affected. It is apparent that there is a lack of information as to proper dimensions that is commonly accepted as authoritative.DISCUSSIONTable 1 gives the minimum furnace-setting heights required by various cities for mechanical underfeed stokers installed under H.R.T. boilers. Figure 1 shows a typical installation. The dimension given for each case is the distance from the dead plate of the stoker to bottom of boiler shell, unless otherwise noted. As shown in the table, different cities use different size-classification systems; it is not possible to make complete, exact, direct comparisons. Table la gives a comparison for various cities, showing the approximate percentage difference in H.R.T. furnace-setting heights required from those recommended by the Stoker Manufacturers' Association arbitrarily chosen to serve as a basis of comparison. The percentages are approxi¬mate because they were calculated as if all heights as given were measured from the dead plate of the stoker. In two cases a lower height is permitted, in a number of cases the height may be the same, and in a number of cases the height must be greater. The percentage increase goes to 100 in one case. Lack of uniformity is quite evident."

Mar 1, 1950

By W. J. Kroll

The production of beryllium metal and its alloys is one of the most difficult tasks in metallurgy. In this report we shall examine the progress made in this work- in the last 15 years; taking into account the outstanding publications, including; those of the patent literature, and the information obtained during our 20 years? experience with this metal. The difficulties experienced' in producing elementary beryllium derive from the physical nature as well as from the chemical behavior of the metal and its compounds. Its oxygen affinity is about the same as that of calcium and a little higher than that of magnesium. Its chlorine affinity is much lower than that of magnesium, about equal that, of manganese, and little higher than that of aluminum. The sulfur and nitrogen affinity is probably almost the same as that of calcium for these elements, and beryllium carbide is probably more stable than aluminum carbide, A14C3. The intermetallic affinity of beryllium may be given in descending order, as follows: Nickel - copper - iron. It forms eutectics with -aluminum and silicon as well as with silver. It does not alloy with magnesium and only partly with calcium. Its oxide melts at 2,570° C., but CaO and BaO form readily fusible eutectics with BeO(65).3/ No igneous solvents are known for BeO, which behaves id this regard like Mgo. The beryllium silicate is a strong compound, the aluminete much less so; however, CaO easily displaces Be in the heated mixtures. The Anhydrous chloride hydrolyzes, and it cannot be made from aqueous liquors. It sublimes at 488° C, and melts at 405° C., The fluoride, which, is very Soluble in water, hydrolyzes also, but a kind of oxyfluoride of the approximate formula 2 BeO?5 BeF2 can be made from solutions by dessication. The fluoride melts at 800° C, and boils above 1,100° C. It forms very stable double fluorides with alkalifluorides, which have very low melting points and are fairly soluble in water. They are more stable than the analogous fluosilicates and the sodium fluoaluminate cryolite.

Jan 1, 1945

By Beatrice L. Lukens, David Schlain, John D. Prater

"The electrolytic manganese process developed by the Bureau of Mines4/ and now in use in the commercial plant of the Electromanganese Corp. at Knoxville, Tenn., and in the Bureau of Mines pilot plant5/ at Boulder City, Nev., involves the electrolysis of a solution of manganese sulfate and ammonium sulfate in a diaphragm-type cell. Metallic manganese is deposited on the cathodes, and sulfuric acid is produced at the anodes.. The spent electrolyte contains, in addition to the sulfuric acid, approximately 30 percent of the manganese and most of the ammonium sulfate originally present in the feed solution. This spent solution is used to leach fresh ore that has previously been given a reducing roast. The resulting leach liquor is purified and returned to the cell.Since the presence of small amounts of certain impurities in the electrolyte may be very detrimental to the electrodeposition of manganese, the purification of feed solution is a very important step in the process. According to the purification method6/ now in use in the Bureau of Mines pilot plant at Boulder city, Nev., cobalt, nickel, iron, arsenic, lead, copper, etc., are removed by precipitation as sulfides at a pH of 6.0 to 6.5. Residual sulfides and colloidal material are removed from the resulting solution by ferric hydroxide formed by adding a small amount of iron sulfate and passing air through the solution. Feed solution purified in this way contains less than 1/2 mg.-per liter-of such impurities as arsenic, iron, cobalt, nickel, copper, etc., and is pure enough to give consistently excellent manganese deposits.Although this purification scheme has given satisfactory results at the Boulder City pilot plant knowledge of the specific effects of various impurities would be valuable. Such information would be useful in diagnosing the causes of cell room operating difficulties, and might aid in the recognition and correction of impurity difficulties arising from the use of new ores.. The purpose of this investigation was therefore, to study the effects of various concentrations of some common impurities.Since the effects of some impurities may not be apparent during short deposition periods and since harmful impurities often cause erratic results rather than consistently poor ones, it was believed that conclusions concerning the effects of impurities should be based upon the results of a fairly large number of 20- to 24-hour tests. Because of the time required for such tests, it was necessary to limit the scope of the work to a few of the more common impurities."

May 1, 1946

By Albert W. Deurbrouck

This report describes the preparation characteristics of the Pittsburgh and Upper Freeport coalbeds in Hancock , Brooke , Ohio , and Marshall Counties , W. Va . Over 4.5 million tons of coal was produced in these four counties in 1962. Most of this production came from the Pittsburgh coalbed . Twelve coal samples were collected for this study , 11 from the Pittsburgh bed and 1 from the Lower Freeport bed . Two of these samples could be upgraded to produce metallurgical - grade coal . The sulfur content of the Pittsburgh- bed coals was generally excessive --as high as 4.9 percent in the raw coal and 3.19 percent in the float 1.30 specific gravity fraction . The rank of the coals in this area ranges from high-volatile A to high-volatile B bituminous .

Jan 1, 1964

By Michael Sokaski, M. R. Geer, H. F. Yancey

This report is one of a series describing investigations by the Federal Bureau of Mines of the performance of various types of coal - cleaning equipment ; other reports in the series are listed in the bibliography . The information in these reports is useful to the coal industry and the manufacturers of coal - cleaning equipment in several ways : First , it assists the coalpreparation engineer who is planning a new plant to select the type of process best suited to the requirements by enabling him to forecast the yield and quality of clean coal obtainable with each type of equipment . Second , the information serves as a yardstick by which the performance of a plant can be judged and thus helps determine whether it is operating at satisfactory efficiency . Both these functions promote better coal - preparation practice ; that is , they help provide coal of more suitable quality for the market and likewise minimize the waste of good coal . This serves the interest of conservation with which the Bureau is vitally concerned . The present report deals with three plants using the Tromp dense - medium process , named after its inventor , K. F. Tromp , who developed the process in the Netherlands in 1936.5/ Selection of this particular dense -medium process for investigation was entirely a matter of convenience , and reports dealing with other dense -medium systems are planned for the future . Two baths are employed in one of the plants investigated . The first of these , handling 6- to 3 - inch coal , exhibited an exceptionally sharp separation between coal and impurity . This was characterized by an error area of 12 and a probable error of 0.023 . In the second bath , treating refuse from the

Jul 1, 1960

By J. H. Maysilles

The Bureau of Mines is conducting research on various technologies to recover alumina from domestic resources for feedstock to existing aluminum smelting capacity as a means to reduce dependence on imported bauxite, which represents 93 pct of U.S. aluminum requirements. One of the more promising technologies being investigated is the hydrochloric acid leaching of kaolinitic clay. In the hydrochloric acid leaching technology, alumina is recovered from iron-free aluminum chloride leach liquor and separated from impurity elements by sparging the liquor with HC1 gas to crystallize aluminum chloride hexahydrate (ACH). A large-scale crystallizer with a 336-gallon usable volume was constructed and operated to obtain engineering and design data for potential scale up and to demonstrate the ability of the technology to produce specification grade alumina. Test campaigns involving about 1,400 hours of operation were completed. ACH meeting all chemical purity requirements could not be produced by a single crystallization, but was produced by recrystallizing the product from the calcined kaolin clay leach liquor. Product crystals with a size distribution of more than 80 pct plus 100 mesh and 65 pct plus 65 mesh were made at a rate of 10 pounds of ACH/(hr)(ft3). The zirconium tube heat exchanger used to maintain constant process temperature operated with an over-all heat transfer coefficient of 420 to 500 BTU/(hr)(ft2)(°F).

Jan 1, 1981

By Kim B. Shedd

The Bureau of Mines measured fiber dimensions on crocidolites (riebeckite-asbestos and magnesioriebeckite-asbestos) from the world's four crocidolite mining regions. The objective of the study was to determine whether there are measurable morphological differences between crocidolite fibers that correlate with the high reported incidence of mesothelioma in miners and mill employees in the Cape Province of South Africa and Western Australia, as compared with little or no reported incidence of this cancer in the Transvaal Province of South Africa or Bolivia. Fiber dimensions measured with the scanning transmission elec-tron microscope showed that crocidolites from Western Australia and the Cape Province have more thin fibers than crocidolites from Bolivia and the Transvaal Province.

Jan 1, 1985

By W. H. Rinkenbach, C. A. Taylor

"Among the recently patented detonating compounds that have been suggested as substitutes for the commonly used fulminate of mercury is the normal lead salt of trinitroresorcin, or styphnic acid. As no data concerning its use or practi¬cability were available, a study of its properties was made in the explosives laboratory at the Bureau of Mines experiment station at Pittsburgh, Pa. This paper embodies the results obtained.Normal lead trinitroresorcinate was first prepared and patented*** by Herz; it probably found some use during the World War, but no record of its performance is available,Preparation of Lead Trinitrpresorcinate.In his patent specifications, Herz states that the normal salt may be obtained in a quantitative way by precipitating a multiple of the equivalent weight of the lead salt of a strong inorganic acid - such as lead nitrate - in the presence of a weak organic acid - such as acetic acid - by heating with a Teak solution of the alkali-metal salts or alkaline-earth salts of trinitroresorcin. Herz gives the following example: 245 grams of dry trinitroresorcinand 290 grams of crystalline sodium carbonate are dissolved in in 18.8 liters of boiling water, to which 77 c.c. of glacial acetic acid is added. The toiling solution is mixed with a boiling solution of 650 grams of lead nitrate in 1.4 liters of water, stirring rapidly; and the mixture is boiled for two minutes, after which it is cooled quickly with constant stirring. The precipitated crystals are then filtered off, washed several times with cold water, and dried."

Oct 1, 1923

By D. W. Bridges

Solvent extraction has become important in recent years as a unit process in extractive metallurgy. The flexibility and simplicity of the technique have attracted widespread attention, and numerous papers describing actual and projected metallurgical applications have been published. However, differences in terminology, procedure, objectives, and standards, as reflected in reports by different operators and investigators, have sometimes made appraisals and comparisons difficult. Consequently, a need appeared for n series of basic reports on the subject. This Bureau of Mines Information Circular is the first of such a series. It deals with the status of solvent extraction in metallurgy, as well as with the rudiments and terminology of the unit operation. In analytical chemistry, extraction of molecular species from aqueous media by immiscible organic solvents has been used for many years to separate and determine chemical elements (61).4 Complex chlorides of iron and other metals are readily soluble in ethers and ketones, as are the nitrates of uranium and thorium. Most metals are extractable as complex salts of some organic reagent, such as dithizone, 8-hydroxyquinoline, or cupferron.

Jan 1, 1962

By F. S. Karn

Conditions necessary to obtain optimum yield of useful products when coal is rapidly heated to extreme temperatures by laser irradiation were determined by the Bureau of Mines. Product distribution and yield were investigated as functions of several variables. Low-rank coals with high-volatile matter gave highest total gas yields. Medium-rank coals gave the highest yields of H2 and CA and low-rank coals gave highest yields of CO and C02. Macerals gave gases of approximately the same composition, but the total gas yield increased in the order fusinite, micrinite, vitrinite, and exinite. Total gas and C2H2 yields varied inversely with particle size. The addition of nominally inert gases such as Ar, He, N2 increased yields of H2, C2H2, and total gas. Metals such as nickel and platinum had little influence on the rate of coal decomposition. Total gas yield increased with total energy of irradiation, and the ratio of C2H2-CH4 increased with concentration of energy. A study was also made of the irradiation temperature, and a material balance was calculated.

Jan 1, 1970

By Michael J. Magyar

The Federal Bureau of Mines has developed a hydrametallurgical method to recover aluminum, aluminum oxide, and fluxing salts from aluminum salt slags. The slag is leached with water at room temperature to produce a saturated brine slurry. Screening of the slurry yields an aluminum-rich fraction that can be returned to the dross furnace. The remaining slurry is vacuum filtered, yielding a clear brine solution and an aluminum oxide filter cake. Evaporation of the clear filtrate produces a high-purity fluxing salt for reuse in the dross furnace. Over 80 pct of the metallic aluminum is recovered in the aluminum-rich oversize fraction, while essentially all the fluxing salts are recovered by evaporation. This report contains the final results of an investigation on a process research unit scale, an economic evaluation of the method, and recommendations to further improve the process.

Jan 1, 1979

By I. Liebman

The Bureau of Mines conducted experiments on coal dust explosion suppression. The investigation took place on a beltway in the double-entry of the Bureau's Experimental Mine. Using conditions that simulate those in a working mine, the investigation showed that a coal dust explosion can be readily initiated in a conveyor belt entry. Also, the explosion can spread into adjacent entries through opened crosscuts (stopping destroyed by explosion) to propagate for long distances even though the adjacent entries are rock dusted in compliance with regulations. Passive water barriers (water-filled tubs) were found to be effective in suppressing explosions on a beltway; however, barrier efficiency was reduced by opened crosscuts. The study indicated that the beltway barrier should be the distributed type consisting of continuous rows of water-filled tubs covering long distances along the entry. A plan is outlined for the installation of a water barrier system in a working coal mine for the protection of a beltway.

Jan 1, 1981