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By C. H. Riggs

This petroleum-engineering report of the Atlanta oil field in BO them Arkansas reviews reservoir conditions and pressure-production history of one of the important Smackover limestone fields in southern Arkansas. The study of the field was made and the report prepared to aid operators in this and similar fields to increase the efficiency of recovery through the application of better engineering practices. A similar study of the Magnolia field in Arkansas by Carpenter and Schroeder was the first of these reports prepared under a joint agreement between the Arkansas Oil and Can Commission and the Bureau of Mines. The increasing demands for petroleum and its products and the steadily increasing cost of discovering and developing oil field; emphasize the importance of conserving known reserves of oil and gas. In recent years vast improvements have been made in the technique of oil recovery, both by better utilization of the natural energy stored in the reservoir and by improved methods of applying external energy to the reservoir system. This report may aid in oil conservation by careful evaluation of the several factors that did or did not contribute the greater recovery in the Atlanta field and by suggesting improvements in production methods and applications.

Jan 1, 1949

By W. W. Agey

This report summarizes results of bench-scale metallurgical studies by the Federal Bureau of Mines on three composite samples representative of the low-grade manganese ores purchased by the General Services Administration (GSA) and stockpiled at Deming, N. Mex., and Wenden, Ariz. Bench-scale flotation tests at the Salt Lake City Metallurgy Research Center showed that all three composites could be beneficiated by flotation to recover 88 to 90 percent of the manganese in concentrates that assayed from 38.5 to 39.0 percent Mn, 10 to 12 percent insoluble, 5 percent CaO, 3 to 5 percent Fe, and 1.3 to 1.7 percent combined Pb plus Zn plus Cu, Sintering studies indicated that specification-grade material could be made from these concentrates by sintering above 1,000° C, and adding either sodium or calcium chloride to the charge to insure removal of enough lead and zinc to meet the specifications.

Jan 1, 1962

By R. G. Knickerbocker, C. T. Baroch, A. W. HACKWOOD

The difficulties inherent in the production of alumina by the formation of potassium alum and its subsequent thermal dehydration and decomposition have been overcome , to a large extent , in a process developed at the Boulder City Station of the Bureau of Mines . This process is applicable to the reserves of alunite known to occur in several Western States and , possibly , to certain clay and low-grade bauxite deposits known to exist in this country . The operations sequence of the process is shown in the flow sheet (fig . 1) . Only those steps included within the heavy line are considered in this report . Four different procedures for dehydration of alum were investigated ; ( 1 ) Spray drying , ( 2 ) rotary - kiln drying , ( 3 ) dry grinding in a thermal ball mill , and ( 4 ) dehydration in the vertical- column flash dehydrator . Based upon fuel requirements and other practical considerations , the vertical- column dehydrator , or some modification of its operating principle , offers the botter possibility for commercial use .

Feb 1, 1946

By Gregory J. Chekan

The U.S. Bureau of Mines is investigating longwall panel and gate road layouts to increase coal recovery and reduce multiple-seam interactive problems. This report presents design practices for longwall mining multiple seams to provide mine planners and operators with practical guidelines for designing productive longwall mines. Key aspects of mine design that control longwall interactions are examined, including sequencing of seams, design of gate road pillars, and orientation of gate roads and longwall panels. Theories that describe stress transfer between multiple scams and the mechanics of interaction are addressed in relation to geology. Common longwall designs were further investigated using a boundary element model, MULSIM/NL. The model provided insight into relative stress transfer and distribution that occurs between longwall operations in multiple seams. Findings from the model show that (1) a longwall panel should be mined from the gob to the solid coal of an overlying mine, because the stress concentrations are lower; the approach angle should be kept under 30°; and (2) when mining in descending order, superpositioning gate roads usually produces the worst stress condition. To prevent this, the overlying isolated gate roads should be positioned from the centerline toward the headgate side of the underlying panel.

Jan 1, 1993

By R. E. Heithecker, D. B. Taliaferro

"INTRODUCTION Recovery of core specimens from subsurface formations and their subsequent analysis are important aids in efficient development and operation of oil and gas fields. Gore specimens first were obtained mainly for the geologic information they revealed; now they are analyzed to determine many of the physical characteristics and conditions of the subsurface formations as well. Cores recovered from the producing formations may be analyzed for porosity, permeability, oil content, ""connate"" water content, and other physical and chemical properties of the formation, all to the end of furnishing enough data for making reliable estimates of the quantity and avail¬ability of oil and as within a reservoir and in devising efficient means for their withdrawal.Examination of bottom-hole samples of oil gives valuable information concerning the amount of gas in solution in the oil within the reservoir and the resultant shrinkage of the oil when the gas is released. Producing characteristics of reservoirs nay be determined by means of subsurface pressure and temperature gages and measurements male at the wellhead; however, unless reliable core analyses are available, these data have only limited use in any quantitative study of reserves. In such a study the quantity of oil, gas, and water contained in a unit volume of the reservoir formation is extremely important. Although reliable methods of analyzing cores have been developed and the data thus obtained are valuable, their applications become more limited or reservoirs at higher temperatures and pressures are discovered. This condition results almost entirely from the fact that in recovering a core from a formation of high pressure and temperature by present methods a large part of the fluid content of the core is lost or contaminated to an unknown extent. For a number of years most petroleum engineers have held that if this loss and contamination of the fluid content of a core were eliminated, the value of core analyses would be increased greatly."

Nov 1, 1939

By Robert M. Busche

[Recent developments in the gasification of coal, both by the Bureau of Mines and American industry, have intensified interest in the thermodynamic and kinetic principles necessary for understanding the reaction mechanism and rates and the physical changes that take place. In the course of a Bureau of Mines study of the kinetics of coal gasification at the Synthetic Liquid Fuels Demonstration Plant, Louisiana, Mo., a bibliography of approximately two references was compiled. They are listed n this publication and refer both to American and foreign sources.]

Jan 1, 1952

By K. Hennings

Noise from vibrating screens is generated in two ways: 1) Noise due to the material being processed and, 2) noise from the screen itself. Non-metallic decks had been shown previously to reduce material noise. The noise reduction and change in screening performance was quantified for six non-metallic decks using dolomite, granite and coal as the materials. The non-metallic decks were from 2 to 7 dBA quieter and from -1 to +10 percent less efficient as compared to a steel wire cloth deck of the same open area. Damping of the sidewalls and isolation of the drive mechanisms had been shown, in a development configuration, to reduce the noise of the screen itself. Tests of four prototype damping treatments gave reductions up to 4.9 dBA and the mechanism isolators gave an additional 2.1 dBA. The treatments were successfully life tested in two ways: 1) Lab tests to a simulated 25,000 hours were conducted on samples of the treatments in a corrosive salt spray to simulate coal plant wash water and, 2) the full size treatments were run on a full size screen for 5,000 hours.

Jan 1, 1980

By B. C. Burgess

This paper, describing the milling practices at the Minpro plant of the Tennessee Mineral Products Corporation, Spruce Pine, N. C., is the first of a series being prepared by the U.S. Bureau of Mines on feldspar milling methods and costs in the various feldspar producing areas in the United States. It describes not only the latest practices in feldspar grinding but includes studies of the cost of producing ground feldspar. These cost studies, obviously of interest to every consumer and purchaser of feldspar and to all feldspar grinders, are also of value to the small operator, who is generally prone to understimate his real costs. It describes the latest practices in feldspar milling and includes detailed costs of grinding. The cost tabulations presented show operating expenditures only and not total production costs. Details of costs are given only to the extent that they are essential to the technical discussion and study of the methods employed. A description of the recently installed milling unit for the preparation of granular glasspar by graded crushing, and magnetic separation is of particular interest. It illustrates how highly specialized feldspar milling has become, and to what an extent grinders are going to supply consumers with the products best suited for their particular needs.

Jan 1, 1931

By J. L. Holman

In conjunction with its research program on separation, recovery, and recycling of metal, mineral, and energy-based materials in urban refuse, the U.S. Bureau of Mines is developing means to reuse and recycle plastics discarded in raw municipal waste. Experimental work on plastic waste from a community collection has produced some guidelines for systematic methods of processing, including air classification, cleaning, separation, and use or disposal. Sink-float methods are a practical means of separation into types. Methods for final disposition of the plastic waste include refabrication, thermal decomposition, and incineration.

Jan 1, 1972

By Walter J. Huff

"INTRODUCTION The technical studies conducted by the Explosives Division of the Bureau of Mines have been summarized in a series of publications issued annually for the past 10 years. 3/ The following account covers studies undertaken from July 1, 1944 to June 30, 1945. The work is set forth under a number of main headings to correspond to the organizational structure of the division, the various activities being under the immediate direction of unit chiefs, who report to the author. Specific credit it due to the unit leader and his assistants.Determination of Ignition TemperaturesThe ignition temperature of mixtures of isobutane and air were determined by the static method using a 131-cc. quartz bull. 5/ The results obtained follow: Prevention of Benzene-Air Explosions by Addition of Nitrogen and Carbon Dioxide The elimination or mitigation of the explosion hazards of combustible gases is a part of the work undertaken by the Bureau of Mines in promoting safety. Explosions can be prevented by the maintenance of concentrations that lie outside the inflammable limits. A procedure has been developed whereby the inflammable limits of many complex gaseous mixtures may be calculated in a rather simple manner without requiring toilsome laboratory experiments. This procedure has been outlined in a number of previous publications. 6./ During the fiscal year under review, essential data required for the calculations of complex combustible gas mixtures containing varying percentages of benzene were obtained. Benzene vapor is a normal constituent of many manufactured gases and is widely used in the solvent industry and in the manufacture of high explosives."

Oct 1, 1946

By Shail J. Butani

In 1986, the Bureau of Mines conducted a probability sample survey, Mining Industry Population Survey, to measure such employee characteristics as occupation; principal equipment operated; work location at the mine; present job, present company, and total mining experience; job-related training during the last 2 yr; age; sex; race; and education. The population estimates are necessary to properly analyze the Mine Safety and Health Administration (MSHA) injury (includes illness and fatality data) statistics; that is, to compare and contrast injury rates for various subpopulations in order to identify those groups that are exhibiting higher than average injury rates. This report uses the survey's results to characterize the U.S. coal mining workforce from March through September 1986. A companion report, Information Circular (IC) 9193, "Characterization of the 1935 Metal and Nonmetal Mining Workforce:' provides similar information for the U.S metal and nonmetal mining industry.

Jan 1, 1988

By Raymond B. Ladoo

Cne of t·: . .:: i::,portt recent developrr.ents in the feldspar industcy l:.a.s beer. tl:.e r,:ipid. rise of Ne·N H.v-:psr.ire as a. feldspar producing State. Tl:.e unusual size and purity of t: e deposit now 'being worked ne3.r Keene, and tr.a i.nproved metl:.ods ot:' rr.ining srd ir,illing used l:.ave been responsible foe tt.is situation. ti'eldsp'.:l. w'ls occ':tsiona.lly produced sorr.e ye1rs ago in srr.a.ll (tuantities in New Hrunpshi :e, but t::.e State had not been considered a producer of" feldspar ui til lS3l. In the s::ring of tr .. at yea!', t:.e '[eane iic Products co. of Keene, N.H., beg3Il in a srr.9.ll way tl:e production of feldspar fro:n t1eir property in Gilsum, H.H., whicr. l-.a.d long been opera.tei a.s a :tl.ca mine. The purity of the feldspar at enoe '\ttracted f''.lvorai)le attention. and tt.e production of crude ore rapidly in­ cre'.\sed. Early in 1922, a new company, t'he Golding-Keene Co,

Sep 1, 1922

By W. W. Adams

The year 1937 was signalized by increased employment in the metal-and nonmetal-mining 4 industry of the United States. Measured by the number of men working, there was a 17-percent gain in employment compared with 1936. In total number of man-hours worked at all mines, the gain was slightly over 18 percent. Hazards connected with mining resulted in more accidents to the workers than in 1936, but the increase in number of accidents caused only a slight rise in the accident rate because of the much larger increase in the number of man-hours worked. In fact, the fatality rate per million man-hours of exposure was lower in 1937 than in 1936, but the rate for nonfatal injuries increased slightly.

Jan 1, 1940

By Allan M. Johnson

Case histories were used to document and evaluate deficiencies in underground mine closures which have resulted in post-operation problems such as subsidence shaft failures, acid or toxic water drainage and others. Three different underground mining districts in the United States were investigated; 1) an iron mining district in Michigan 2) coal mining districts in eastern Ohio and southern Illinois and 3) three metal mining districts in central Colorado. Previous work in the Michigan district on problems with subsidence and acid water drainage provided the background from which the concept for this project was developed Student investigators working towards their MS degrees in Mining Engineering did the work on the eastern coal and western metal districts. The combined studies show that problems from acid water drainage, subsidence and inadequately protected mine shafts are the most severe and widespread. Suggestions of a technical nature are presented as partial solutions to some of these problems. It was determined that pre-closure evaluations could result in the identification of some potential problems that may occur after the mine is closed. Early recognition of these problems would be an advantage for at this time more options are available to the mine operator to either prevent them or to plan for their occurrence. Mine closure and reclamation should be considered as a part of mining and be incorporated in the mining plan. This would result in reduced environmental impact and would be achieved at a lower overall cost to the mining companies and to society. The role of water in the occurrence of several types of subsidence during mine flooding was significant at some mines in the Michigan district. These mechanisms which involve, friction reduction, gravity loading, overburden transport and hydraulic forces in a flooded mine probably have a broader effect than is currently recognized. Control of these processes may offer some interesting options during mine closure. It is recognized that technical solutions alone cannot provide all of the answers to problems associated with underground mines. Education, modified attitudes on the part of regulators and operators, and a more realistic perception of the importance and value of mining by the general public are also needed.

Jan 1, 1983

By Laird Crocker

This report describes a study of beryllium recovery from sulfate leach liquor by di-2-ethylhexyl phosphate (EHPA) solvent extraction in conjunction with caustic stripping. The work was one phase of Bureau of Mines research on process development for Spor Mountain, Utah, ores. Solution for the solvent extraction studies was prepared by sulfuric acid leaching of ore containing 0.6 pet BeO, Before solvent extraction of beryllium, the leach liquor was treated to prevent coextraetion of iron by either (1) removal of ferric iron by amine solvent extraction or (2) reduction of ferric iron to nonextractable ferrous iron by treatment with sulfur dioxide. Beryllim was extracted from the aqueous leach liquor by countercurrent multistage contacting with a kerosine solution of EHPA. The loaded organic solution was stripped with sodim hydroxide solution. Subsequently, beryllium hydroxide was precipitated by boiling the sodium beryllate strip solution and converted to beryllium oxide of 98 pct BeO-grade by calcining. Material of this grade can be directly processed into beryllium-copper alloy or be used as starting material for further refining to produce high-purity, nuclear-grade beryllium. Over 90 pct of the beryllium contained in the leach liquor was recovered as beryllia.

Jan 1, 1963

By W. W. Adams

Two important facts stand out as features of the metal- and nonmetal-mining4 industry of the United States in 1941 as compared with 1940: First, the number of employees and man-days of employment increased; second, accident-frequency rates, both fatal and nonfatal, decreased. Reports from mining companies to the Bureau of Mines covering underground, open-pit, and surface operations for 1941 re¬vealed the largest number of men employed since 1926 and the largest number of man-days worked since 1929. The combined fatal and non¬fatal accident-frequency rate for 1941, calculated on a basis of one mil¬lion man-hours of exposure to hazard, was (except for 1931 and 1932) the lowest since 1911, the earliest year for which figures are available. During this 31-year period, only 1938 and 1939 showed lower fatality rates, and only 1931 and 1932 had lower nonfatal-injury rates. Operating companies reported that 9,620 mines were active during all or some part of the year. These employed 125,290 men, an increase of more than 4 percent over 1940. The total volume of work performed at all mines, measured in terms of man-shifts, increased to nearly 32 million, a gain of 10 percent; man-hours of employment rose to almost 254 million, an increase of 10 percent over the 231 million man-hours worked in the previous year. The year's operations resulted in an average work-year of 255 days per man, an increase of 13 days per employee over the average working time in 1940. Although the 8-hour day prevails generally at most mines, the industry as a whole averaged 7.94 hours per shift, as in 1940.

Jan 1, 1944

By T. M. Barczak

One of the primary goals of Bureau of Mines research is to reduce the cost of coal mining by improving the efficiency of longwall supports. One method of achieving this goal is the optimization of stress distribution within the support structure, resulting in a lower overall weight, more fully stressed shield. However, before stress optimization can be initiated, load conditions must be defined that cause maximum stress in the various support components. A finite-element model of a longwall shield was used to identify these critical load conditions. These load conditions were then evaluated in the Bureau's mine roof simulator (MRS) by instrumentation of a longwall shield and measurement of strains in each of the shield components. The critical (canopy-base contact) load conditions were identified that can cause structural failure at less than rated shield (hydraulic yield) capacity. Comparisons were made between full-contact and partial-contact load conditions. Other parameters investigated included the stiffness of the contact material, changes in shield geometry, rate of load application, and effects of horizontal constraint. Conclusions were drawn regarding the structural integrity of the major shield components and potential for stress optimization.

Jan 1, 1987

By Harold M. Smith

Natural gas has been used as a fuel and source of energy almost from its discovery, but its use as a chemical raw material may be said to have begun in 1918, when Brooks and Humphrey3/ showed. presence of alcohols in the diluted acid oil obtained by the sulfuric acid-treatment of cracked petroleum distillates. However, development of the utilization of natural gas for chemical syntheses was slow, partly because erroneous ideas existed regarding the nonreactivity of tine hydrocarbons composing natural gas. Data accumulated by petroleum chemists throughout the world, particularly since about 1930, have shown that these hydrocarbons will react when activated by the effects of heat, pressure, chemical reagents, and light; also that the reactions can be made to proceed of practicable speeds and to provide good yields of useful products with moderate operating conditions, especially if catalysts are employed. As those results became known, the possibility of a synthetic organic chemical industry based upon these reactions became apparent, and today this industry is large and growing rapidly in importance. In this paper the story of the manufacture of chemical products from natural gas is told simply in graphic form. The industry is developing so rapidly that soma products may have been omitted, but every effort has been made to include all that are important or likely to become so. The difficulty of keeping information of this tape up to date is shown by reference to an information circular4/ or, the sore subject published by the Bureau of Mines in 1930, in which the important products are shown on a single chart, where as five charts are employed for the cane purpose at present.

Jan 1, 1940

By N. S. Dalal, X. Shi

"Electron spin resonance (ESR) measurements on solutions and isolated powders provide direct evidence for the involvement of Cr(V) species in the reduction of Cr(VI) by NAD(P)H. ESR analysis of an isolated Cr(V)NAD( P)H solid yields 6 11 = 1.9831 and 6.i. = 1.9772, indicating that the unpaired electron occupies the d22 orbital of the Cr(V) ion, with square-pyramidal geometry. Addition of hydrogen peroxide (H2 0 2 ) to the N AD(P)HCr( VI) reaction mixtures suppresses the Cr(V) species and generates hydroxyl (""OH) radicals. The ""OH radicals were detected via ESR spin trapping, employing 5,5-dimethyl-1-pyrroline-N-oxide and a-(4-pyridyl-1- oxide)-N-tert-butylnitrone as spin traps. The dependence of Cr(V) and ""OH radical formation on the H20 2 and Cr(VI) concentrations indicates that the Cr(V) species react with H20 2 to generate the ""OH radicals. Similar results were obtained by using various diols (arabinose, cellobiose, FAD, fructose, glyceraldehyde, ribose, and tartaric acid), a-hydroxycarboxylic acids, and glutathione. Investigations with superoxide dismutase showed no significant participation of 02 in the generation of OH radicals. These results thus indicate that the Cr(V) complexes, produced in the reduction of Cr(VI) by cellular reductants, react with H20 2 to generate ""OH radicals, which might be the initiators of the primary events in the Cr(VI) cytotoxicity.In this paper we report an electron spin resonance (ESR)3 spectroscopic detection of Cr(V) species in the reduction of potassium dichromate, henceforth called Cr(VI), by NAD(P)H and other diols. Also reported here is the detection of the hydroxyl (""OH) radical in the reaction between hydrogen peroxide (H2O 2) and a variety of Cr(V) complexes. This work was undertaken because while the reduction of Cr(VI) to lower oxidation states has been suggested as a key step m the mechanism of Cr(VI) toxicity, mutagenicity, and DNA alteration, the details are not yet clear (1-5).Earlier studies on the mechanism of Cr(VI) reduction in cellular systems include those on the reduction of chromate by microsomes (6-8), rat liver DT-diaphorase (9), and aldehyde oxidase (10). All these studies imply that Cr(VI) can be reduced to Cr(Ill) by cellular constituents. Regarding the mechanism of Cr(Vl) carcinogenicity, Jennette postulated that Cr(V) is the ultimate carcinogenic form of chromium compounds (8). This conclusion has led to many further investigations of the formation of Cr(V) in the reduction of Cr(VI) under biologically relevant conditions (11-33). More recently, however, Kawanishi and co-workers (34) have investigated the mechanism of DNA cleavage induced by Cr(VI) in the presence of H20 2 and have argued that it is not Cr(V) itself that is carcinogenic, but it is the reactive oxygenated species (02, 10 2 , ""OH) (produced by the decomposition of the Crv(02) ¾ - ion) that cause the DNA alteration."

Jan 1, 1990

By Irven A. Jacobson

This literature survey consists of references dealing with gaseous state thermal decomposition reactions of organic nitrogen and sulfur compounds. The reference source for the survey was the Chemical Abstracts from 1930 to 1956, inclusive. Original articles were not studied. The starting date was set at 1930 because previous to this time much of the work is questionable. This report is in three parts: Part I lists nitrogen compounds; Part II, sulfur compounds; and Part III, compounds containing both nitrogen and sulfur. The organization of the classes of compounds is alphabetical: Part I - amides, amines, amino acids, ammonia, azides, azines, azo compounds, heterocyclic nltrogen compounds, hydrazine, nitrates, nitriles, nitrites, nitro compounds and miscellaneous nitrogen compounds; Part II - disulfides, sulfides (including double and triple sulfides), thiols, thiophenes and xanthates; Part III - thioacid amides, thiazoles, thiocyanates and thiuram disulfides. A class formula is included with each class name. The R's used in these class formulas may refer to hydrogen or to the same or different radicals when more than one R appears.

Jan 1, 1960