Search Documents

By R. R. Wells, G. M. Potter, A. O. Ipsen

This paper gives results of laboratory and pilot - plant investigations of concentration of western manganese ores during the Bureau of mines manganese-development program initiated in December 1940. The data summarize results obtained from laboratory investigation of concentration of ores from three properties in southeastern Arizona . The high - grade Gray - claims lot B ore , a product of hand sorting , is marketable directly or after sintering treatment . Intermediate - grade lot A selectively mined ore would be marketable after sintering as a plus 35 percent manganese produce , but gravity concentration methods were employed effectively to produce high - grade manganese concentrates with over 80 percent recoveries . Complex association of fine - grained manganese oxides , calcite , and fluorite in a siliceous ground mass limited the recovery of high-grade manganese concentrates obtainable from the low-grade Pyrolusite -group ore . A recovery of 63.7 percent of the manganese was made by flotation in a concentrate that sintered to plus 48 percent manganese grade . The low-grade Davis ore contains iron and manganese oxides too intimately associated to permit production of marketable manganese products . However , good rejection of calcite gangue was obtained by flotation , and the enriched manganese - iron product might have value as a spiegeleisen ore .

Feb 1, 1946

By E. B. Kester

A study of the composition of the corresponding fractions of a primary and a high-temperature tar was undertaken to throw light on the net results of the pyrolysis of the primary products of coal decomposition in high-temperature coking practice, with reference both to total quantities of the chemically similar constituents and to their distribution throughout the boiling range. No exactly parallel investigations are on-record. The distribution of substances in high-temperature tars, however, is fairly well understood. Such tars are more or less similar, for they consist of the more stable phenols, aromatic and olefinic compounds resulting from the pyrolytic decomposition of a wide variety of primary tar constituents. For example, from a typical distillation curve for high-temperature tar phenols it may be seen that the greatest portion of the phenols distills between 180° and 220° C., a fairly narrow range. Low-temperature tars, on the other hand, are more complex, and hence exhibit dissimilarities from one to the next. Edwards, who has made a study of the acids, bases, and neutral oil of four low-temperature tar distillates, shows that the bases and neutral oil are evenly distributed among the fractions but that the concentration of the acids is greatest in the 200° to 230° fraction. Morgan and Soule find that in tar from the "Carbocoal" process, the 237° to 281° fraction has the highest acid content, whereas Davis and Parry find the 200° to 225° fraction of Freeport tar richest in phenols. Previous investigators have noted the following differences between primary and high-temperature tar: In the latter, naphthalene and anthracene occur in large quantities, the paraffins and naphthenes are negligible, the percentage of higher phenols is much lower than in primary tar, and the lower and more stable aromatic hydrocarbons have increased. In an endeavor to reconcile the change undergone when a primary is converted into a secondary tar, the writers have been unable to find references dealing with the extent of change which any one of the constituents of primary tar may undergo when subjected to secondary heating effects in the presence of other components, and the amount of the more stable compounds that may be expected from a given starting material.

Jan 1, 1932

By A. F. Colombo

The western Mesabi range nonmagnetic taconites containing about 34 percent Fe were evaluated by the Bureau of Mines in a 900-pound-per-hour pilot plant employing a selective flocculation-desliming-cationic flotation technique. The flotation step was a reverse flotation process and involved the flotation of the gangue minerals. The objective of the research was to increase the availability of domestic raw materials for the iron and steel industry. The beneficiated ores yielded concentrates containing 62 to 64 percent Fe and less than 5.5 percent Si02 with accompanying iron recoveries that averaged about 75 percent. Comparable flotation results were obtained with either fresh or 80 to 90 percent reclaimed water. Recycled waters having turbidities as high as 5,000 ppm Si02 did not affect the flotation process. Reclaimed waters containing residual calcium contents of less than 10 ppm gave better flotation concentrates than those containing 15 ppm.

Jan 1, 1976

By Oren C. Baptist, Carlon S. Land, Eliot J. White

The water sensitivity of the oil - gas - producing sandstones in three fields in the Patrick Draw area of southwestern Wyoming was estimated by laboratory testing . The tests used to estimate sensitivity , which is a measure of the loss of well productivity if the producing formation is invaded by fresh water , are : Porosity ; permeability to gas , water , and brines ; saturation characteristics with air displacing water from the samples and by mercury injection ; and identification of clay minerals by X - ray diffraction . Laboratory results indicate that the degree of water sensitivity of the sands in the Patrick Draw, Table Rock , and Desert Springs fields vary , in that order , from moderately sensitive to highly sensitive . The main cause of the sensitivity appears to be the movement of fine particles in the pores , but the swelling of a small amount of an expandible clay mineral may also contribute to the permeability reduction observed in the samples . Laboratory results further indicate that the permeability of the sands to fresh water is seriously reduced if they are first flushed with sodium chloride brine ; calcium chloride brine is less harmful to the sands than sodium chloride brine . The low original permeability of the oil sand in the Patrick Draw field , together with its moderate sensitivity , indicate that the rate of water injection for the secondary recovery of oil will be low . Limited field experience in two pilot - injection wells confirms this prediction .

Jan 1, 1964

By R. R. Sayers

Under compuision of the present urgency to implement the President's promise to make the United States the arsenal for the democracies there is a tendency to demand a relaxation of restrictions on hours of labor and to speed up all industrial processes. The pressure is the more insistent with growing realization of the importance of the time factor in the success- ful prosecution of the war effort and the lack of skilled workers due to (2) operation of the draft, lack of an apprentice system in industry, and loss of skill by workers unemployed for long periods during the depression. With "total" war such as it is today the probabilities are that everyone will be required to exert greater effort (in many instances in activities to which they are unaccustomed) for longer periods than ever before has been necessary. The question arises, "What will be the aftereffects as well as the immediate effects on health, safety, and efficiency?" A review of the literature leaves the impression that this question has not been an- swered completely, especially as regards the ultimate effects. Mechanization, speeding up of industrial processes, mass produc- tion, and the small industrial concerns present many problems to indus- trial medicine. Does the tendency to expect the worker to produce at full speed all the time he is on the job decrease the effectiveness of the shorter working hours and cause undue fatigue, loss of efficiency, and increased accident proneness? The answer is important as this condition is likely to be intensified by the exigencies of the present emergency. According to Viteles (1)3, The increased tension under such conditions of work appears to offset the savings in muscular force made pos- sible by the machine. The tension, the speed, the subject- tion to specialization of work and a rhythm uncontrolled by the individual promote fatigue, characterized by a "decrease in the power to work, a decrease in pleasure taken in work, and a decrease in the enjoyment of the hours spent away from work."' The crowding of workers in temporary structures without proper provision for comfort and health may add greatly to the general fatigue factors already present in many industrial establishments. In 1932 Lockhart (2) stated that the production and maintenance of a healthy, satisfied industrial population is the most urgent necessity, involving problems so serious as to constitute a national task too great economically to be relegated to industrial concerns. If this was true in 1932, it must be doubly so today.

Jun 1, 1942

By Effie T. Kurt, Jack Wright, J. W. Watkins, Cynthia Pearson

"The analysis of water produced with crude petroleum has interested oil producers since inception of the industry. Records of the first analysis of mineralized water produced from an oil-productive formation are obscure, and references to the first use of brine analyses to assist in solving problems of petroleum production are not available in the technical literature. However, many early reports of the Federal Bureau of Mines 5-8/ and. Federal Geological Survey, 9-11/ as well as articles in engineering and geological placed special emphasis on journals ,12-l4/ the importance, interpretation, and application of water analyses.One of the earliest applications of water analyses, and still a major one today, is for identification of intrusive waters in oil wells. This may be done by comparing the chemical constituents of a sample of water indigenous to the oil-productive formation with those of samples from upper, water-bearing formations within the same general area. Some earlier investigators recognized the need for analyzing samples of all waters encountered in drilling operations. Ambrose15/ stated, in part, ""In wells being drilled, the engineer should grasp every opportunity to get a true sample of water from each sand. . .,"" and, ""The waters of each oil field are chemically different from those of another field."" The validity of the latter observation and the importance of the former one have been borne out by comparing the results of analyses of many samples and noting the differences in relative concentrations of like constituents of waters from the same geological formation in different localities or oil pools."

Apr 1, 1957

By J. P. Powell

The application of secondary producing methods for recovering additional oil from known fields has been recognized for many years as important to the economy of the nation. One of the most successful secondary methods is waterflooding, which conserves our natural resources by preventing premature abandoment of stripper leases and revitalizing previously abandoned areas. Waterflooding as a secondary-recovery method was introduced into the Midcontinent region in 1931, and its use as such has become widespread. As with most new methods, the most favorable fields and leases received primary attention, whereas those with viscous oil or less favorable sand characteristics were bypassed. Numerous reports3 4 5 6/ have been published giving the results of individual waterflooding projects, In this report, attention is directed to the effect of a single factor, the viscosity of the oil produced,

Jan 1, 1959

This publication summarizes the research (in-house and contract projects) programmed by the Bureau of Mines for fiscal year 1984 (October 1, 1983-September 30, 1984) under its Health and Safety Technology Program. The objective of these projects is to provide an ordered and sequenced advance toward the Bureau's overall goal of providing the systems technology required to create a more healthful and safer working environment for the Nation's mining and minerals processing workers.

Jan 1, 1983

By Daniel T. Rogers

The Bureau of Mines, in its alumina miniplant project to investigate alumina recovery from domestic, non bauxitic ores, has conducted research on the use of a hydrochloric acid leaching, gas sparging crystallization technology. An important element of this research is the efficient separation of undissolved, siliceous residue from AICI3 -bearing leach liquors by continuous, horizontal, countercurrent vacuum belt filtration. In an effort to calculate material balances quickly and to predict material balances based on different belt filtration configurations, the perfect-mixing-cells-in-series model (PMCS) for calculating material balances around belt filters was used. Because of the porous nature of the solids, the model produced erroneous material balances. Therefore a reliable model, the shrinking voids model, was developed postulating the presence of an unwashable voids liquor volume that decreases with decreasing liquor AICI3 concentration. This volume decrease postulation is equivalent to assuming that dilute liquors flow more freely, causing more voids liquor volume to become washable. Least-squares based computer programs are provided, which are useful not only in producing material balances from plant data but also in predicting balances for untested configurations using the same feed materials.

Jan 1, 1982

By Joseph Berman

The wolframite mineral series was studied to determine the effect of the FeO - MnO ratio on unit cell symmetry and thermal stability. This work was undertaken to evaluate the analytical procedures now in use for wolframite in scheelite and to aid in the development of improved methods of analysis. Wolframite grains were hand-picked, crushed, and screened; impurities were removed by selective magnetic separations using a Frantz isodynamic separator. The samples were further checked by optical spectroscopic and microscopic examination.

Jan 1, 1957

By M. C. Irani

This Bureau of Mines report tabulates methane emissions from U.S. bituminous coal mines with daily emission rates of at least 100,000 cfd according to States, counties, and coalbeds. Most of the methane emitted is from mines in the Appalachian States. Total daily emission in 1975 was 216.3 MMcfd, compared with 227.0 MMcfd in 1971 and 214.5 MMcfd in 1973. Thirty counties in nine States hid daily methane emissions of 1 MMcfd or more. These emitted 93 percent of the total methane. The highest emissions were from Monongalia County, W. Va., which accounted for 18.9 percent of the total. This was followed by Marion County, W. Va., 9.6 percent; Buchanan County, Va., 8.3 percent; Jefferson County, Ala., 6.1 percent; and Washington County, Pa., 5.9 percent. The Pittsburgh coalbed emitted 45.7 percent of the total methane, followed by the Pocahontas No. 3 coalbed with 12.9 percent. The report lists 196 mines, of which 60 had daily methane emissions of 1 MMcfd or more. Included in this compilation are the identification and thickness of the coalbed, methane emission, coal production and ventilation rates, number of drifts, shafts, and slopes used for ventilation purposes, shaft depth, age of mine, and gas-to-coal ratio.

Jan 1, 1977

By Sam S. Taylor, H. M. Smith

"INTRODUCTION In most oil fields, natural gas is the major source of energy causing flow of oil to the well. The amount of gas Produced with the oil generally exceeds actual energy requirements, so that in time the gas reserve of the field becomes seriously depleted and the oil production must be stimulated by some auxiliary means. One of these is to repressure the oil formation with natural gas; or, where a gas supply is not available, often air is used.Although P.ir is a Cheap and convenient repressuring medium, its use sometimes is attended with several disadvantages. First, the return air-gas mixture decreases rapidly in fuel value, often until it can be used no longer as a source of power. At the same time, explosive mixtures may result if recycling is used, causing hazards to life and equipment. Second, some fields experience considerable trouble with the formation of emulsions which become increasingly difficult to treat. Although there is no definite proof that air repressuring always causes these emulsions, many operators are convinced that this is the case. The Petroleum Experiment Station of the United States Bureau of Mines at Bartlesville, Okla., has been interested in problems connected with air-repressuring for a number of years. Some time was spent in studying the so-called ""bad gas""--return,mixture of low fuel value. However, it appeared impossible to attack the problem successfully from this angle, and an approach was made through a laboratory--scale study of direct oxidation of crude oil."

May 1, 1934

By J. A. CoRGAN, J. A. DECARLO

The coal -carbonizing industry is recognized as one of our country's most essential industries , and this position has been achieved through its primary function as a source of supply of special fuels and chemical raw materials . When coal is carbonized at high temperatures in slot - type coke ovens in the absence of air , it decomposes into two main products cokę ... and crude gas . Of these , the more important is coke , a hard, strong, porous solid that remains in the oven after the volatile matter in the coal has been driven out by heat . The hot crude gas carries with it all. of the coke -plant products except coke and has a complex composition in the vapor: state . Its processing , to produce the four principal coproducts of coke (tar , ammonia , light oil, and gas ) , is accomplished by preferential condensation and absorption . Although the principal coproducts of coke tar , ammonia , and crude light oil - - gas, are of secondary importance , their

Jun 1, 1949

By H. H. Schrenk

One phase of Bureau of Mines work in health and safety is promotion of the use of safe, satisfactory, and reliable respiratory protective devices. To insure that such devices will be. available, the Bureau has established schedules of minimum requirements for oxygen breathing apparatus,3/ gas masks,/ supplied-air respirators (hose masks, air-line, respirators, and abrasive blasting helmets, hoods, or masks),5/ and dispersoid (dust, fume, and mist)

Jan 1, 1943

By Tilman M. M.

The effects of substituting cobalt for nickel on the acid corrosion resistance of two types of austenitic stainless steel were determined. Cobalt substitutions to a maximum 2.2 weight-percent were made in types 302 and 309 stainless steels. Total immersion corrosion tests were made in 10 volume-percent hydrochloric acid, and boiling-acid tests were conducted in 65 weight-percent nitric acid and in undiluted glacial acetic acid. For modified type 309 in acetic acid, corrosion rates decreased for additions greater than 0.57 weight-percent cobalt. Corrosion rates increased as cobalt was increased up to about 1 weight percent for modified type 302 in nitric and hydrochloric acids and for modified type 309 in nitric acid, but these rates decreased with a further increase in cobalt content. A gradual increase in corrosion rates with increasing cobalt content was shown for type 302 in acetic acid and for type 309 in hydrochloric acid. Cobalt substitutions in larger amounts (above a ratio of 8 Ni to 1 Co) may increase the corrosion resistance of the austenitic stainless steels.

Jan 1, 1965

By James J. Dowd

The investigation to evaluate the reserves of coking coal in the United States suitable for the manufacture of metallurgical coke is being made by the Bureau of Mines in three parts: (1) To estimate known (measured plus indicated) recoverable reserves of all coking coals; (2) to upgrade marginal coals through effective preparation; and (3) to study the carbonizing properties of coals and coal blends not now widely used for metallurgical coke making. This is the fourth of a series of reports giving the results of studies by counties under phase (1) of the investigation. It covers Armstrong County, Pa., which comprises parts of the Foxburg, Clarion, Brookville, Kittanning, Bural Valley, Smicksburg, Freeport, Elders Ridge, and Indiana quadrangles. (See fig. 1.) A base map for each bed in each quadrangle was made to the scale of 1 inch equals 1,200 feet. Maps of mines, locations of drill holes, bed and total coal thicknesses, and the outcrop of the bed were plotted on the maps. With all available data plotted, isopach lines were drawn to limit areas of known unmined reserves in beds 0 to 14 inches thick, 14 to 28 inches thick, 28 to 42 inches thick, and more than 42 inches thick. These areas of coal reserves also were divided into "measured" and "indicated" categories. All areas in each thickness range and in each category, mined-out areas, areas excluded from the estimate, and areas outside the outcrop were measured by planimeter on the base maps, Estimates of total reserves 14 inches and more thick and maps for individual beds were prepared from these data.

Jan 1, 1951

By R. Wiebe

During a recent investigation the authors were interested in determining: (1.) How many points were necessary to locate the deviation curve for copper-constantan thermocouples within an accuracy of about 0.05° C., used in connection with the "standard" thermocouple of L. H. Adams. (2.) Whether copper-constantan thermocouples showing considerable deviations from the "standard' were consistent throughout their calibration. (3.) How reliable the extrapolated portion is - that is, the interval between -183 and -220° C. of the "standard" thermocouple. It seems that a calibration between 0 and -193° C. can be made within the stated accuracy by determining experimentally the e.m.f. of the particular couple at -78.50°, the normal sublimation point of carbon dioxide, and at -182.97°, the normal boiling point of oxygen. Substituting the values found for the two fixed points in the simple quadratic. Equation

Jan 1, 1931

By M. R. Geer

The Bureau of Mines examined the washability data for 25 Appalachian coals requiring low-density washing to reduce sulfur content to 1 percent, using the distribution-curve method. The purpose was to estimate how closely theoretical sulfur values could be approached, what yields of washed coal could be expected, and the recovery efficiencies that might be achieved. Assuming that the run-of-mine coal would be crushed to 3/8 inch and cleaned in dense-medium cyclones, the calculations indicate that theoretical sulfur contents could be approached closely when cleaning at a specific gravity of separation as low as 1.30. With coals that have favorable specific gravity compositions the recovery efficiency anticipated for cleaning at 1.30 specific gravity is surprisingly high. Similar calculations for cleaning with concentrating tables at intermediate specific gravities indicated that theoretical sulfur contents at 1.50 specific gravity could be approached closely with some coals but not with others. The calculations suggest that operating a table at a specific gravity of separation much lower than about 1.50 probably would be unsatisfactory with most coals.

Jan 1, 1968

By T. F. Anstett

The Bureau of Mines estimated the potential availability of rare-earth oxides (EtEO), including yttrium, and thorium, which is also contained in the rare-earth bearing minerals monazite and bastnasite, from 38 'properties in market economy countries (MEC's). Only nine of the properties evaluated produce or would produce REO as the primary product; the others contain REO as a byproduct, chiefly from mineral sands operations recovering rutile, ilmenite, and zircon. Nearly 77% (2,578,000 mt) of the total 3,355,000 mt of recoverable RE0 evaluated is from producing properties. It is estimated that 21% (705,000 mt) of this total is from properties that could not realize a positive rate of return at the January 1984 market prices for the recovered commodities. At production capacities assumed for this evaluation, the amount of RE0 potentially available from producers ranges from an estimated 46,500 mt in 1986, to a peak of 50,900 mt in 1992, to 49,900 mt by the year 2000. Total MEG production in 1984 was estimated at 40,700 mt. Assuming demand does not increase sharply, producing properties can continue to fulfill overall REO demand through at least the end of this century.

Jan 1, 1986

An accelerated and coordinated program of coal research is believed by many to be a necessary step in assuring coal's proper position in the expanding energy market. The President's Advisory Committee on Energy Supplies and Resources Policy, for example, made the following recommendation: We recognize that coal is a great national asset and endorse a cooperative study to determine what research and development could be undertaken. The coal industry and both Federal and State Governments should participate in this study and its costs. Representatives of the coal industry have agreed that such a study should be initiated. Accordingly, Felix E. Wormser, Assistant Secretary - Mineral Resources, United States Department of the Interior, requested the Bureau of Mines and Bituminous Coal Research, Inc., to conduct a survey of current research on bituminous coal. In addition to this survey, studies were made to determine research projects that would be of value to the coal industry.

Jan 1, 1956