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By G. R. Hopkins

The average quantity of heat needed to refine a barrel of crude oil in 1934 was 638,000 B.t.u., or about as much heat energy as contained in 5 gallons of fuel.oil. Although the total heat utilized in 1934 was slightly above 1933, crude runs to stills increased 4 percent, hence the average requirement per barrel declined from 660,000 B.t.u. in 1933 to 638,000 B.t.u. in 1934 (see fig. 1). The average for 1934 constitutes a new record for firing efficiency, being just under the previous low of 1929. Heat consumption at refineries depends on many factors, of which the trends in yields of gasoline and lubricating oils are probably most important. The yield of gasoline is indicative of activity at cracking plants, which typo of plant utilizes more thou the average amount of heat per gallon of product. The yield of lubricating oils is indicative of the extent to which crude oil is refined; that is, it takes considerably more heat to refine a barrel of crude through lubricating oils than it does to separate only gasoline and kerosene. The yield of gasoline decreased from 43.7 percent in 1933 to 43.4 percent in 1934; on the other hand, the yield of gas oil and fuel oil increased. Although the yield of lubricating oils increased slightly in 1934 the theoretical increase in fuel requirements probably was offset by technical improvements, such as solvent refining. Although no outstanding technical developments of a fuel-saving nature were made in 1934, some progress undoubtedly was recorded. Heat exchangers, an effective fuel-saving device, wore enlarged, and some refiners now take off several cuts before the crude reaches the pipe stills. The total capacity of pipe stills increased 2.5 percent in 1934, and many of the less efficient shell stills were torn out.

Jan 1, 1935

By M. B. Shirts

Bench-scale studies were made on a reductive hydrometallurgical procedure to convert chalcopyrite flotation concentrate to copper metal or a readily leachable sulfide. Reductive conversion of chalcopyrite and dissolution of iron and sulfur were accomplished in hydrochloric or sulfuric acid solution by the addition of metallic copper, iron, or lead. Use of metallic copper as the reductant enabled extraction of 95 and 46 percent of the iron and sulfur, respectively. The products were ferrous iron, hydrogen sulfide, and a copper sulfide. Use of metallic iron or lead as the reductant enabled extraction of 95 percent of both the iron and sulfur. The products obtained with metallic iron or lead were ferrous iron, hydrogen sulfide, and metallic copper.

Jan 1, 1974

By A. W. Ambrose

"Those having an intimate knowledge of the relation between production and consumption of crude oil in the United States have realized for some time that production will not be able to keep pace with consumption. The American public has had this called forcibly to its attention by the increased prices of gasoline and crude oil, and by the recent shortage of gasoline on the Pacific Coast. In substance, each year we are consuming millions of barrels of oil more than we produce, and this deficit must be made to by importations. A careful analysis of the situation makes it evident that we need every barrel of oil that can be produced.Need for the Petroleum Production Engineer.Under present production practices perhaps 80% of the oil still remains in the sand. (See Lewis, J.O., Methods for increasing the recovery from oil sands, U. S. Bureau of Mines, Bulletin 148 p. 8.) Many wells are making water, and even whole pools are being flooded. The burning of fuels under field boilers is not generally efficient, and often gas is not made to do its full duty in bringing the oil to the well.In the past the producer has had to combat these and other problems single-handed. He has been too busy to give them special attention, and he has had little competent engineering advice. Oil, gas, and water occur underground according to certain natural laws. Undoubtedly an engineer, who is familiar with production practices and understands the fundamentals of the accumulation of oil and gas, can be of service to the producer by specializing on certain problems with a view of getting mare oil from the sand. In every other enterprise of similar magnitude the engineer is regarded as a necessary unit to its operation, and he should be so in the production of oil. His field of work should extend to every phase of production in which science and engineering and geology"

Sep 1, 1920

By F. W. Brown

In 1942 the Explosives Division investigated electrostatic hazards associated with the manufacture, storage, and use of explosives. A report was issued in 19454/ presenting the data on the spark sensitivities of explosives. In 1948, the apparatus was redesigned and rebuilt to make the routine testing of explosives safer and more convenient. The rebuilt apparatus is described in this re-issue of the former report. Included are details of construction and a list of parts. PRINCIPLES OF METHOD In normal procedures without special precautions, it is possible for static charges to be accumulated on individuals or on ungrounded equipment or structures.5/ Static charges may be produced in many ways, but they are most commonly produced by rubbing or successive contact and separation of unlike surfaces, at least one of which is usually an insulator.

Jan 1, 1953

By W. W. Culter

"This paper is the outcome of thorough investigation into the value of the previous methods used for deriving production decline curves. It is highly important that methods be employed that are fundamentally sound and also practicably applicable. Six methods commonly used were studied. Some of these were found to be fundamentally in error; some save reliable curves but involved much work and time in the preparation; others gave reliable curves with less time and effort.It was found that of the methods previously employed the ""family curve"" method described in Bull. 134 Amer. Inst. Feb. 1918, pp. 499-500 by Lewis and Beal, was probably the most satisfactory. The now method given in this paper ploys the same principles as the ""family curve"" method, but is mathematical instead of graphical,The engineer and the oil man should carefully boar in mind both the use and the limitations of the average production curve such as is derived by the ""family curve"" method or other methods mentioned. Estimations of future productions or of underground oil reserves of a particular tract or well should be made from the production records of the tract or the well itself wherever such records are satisfactory. The use of the average curve of a district or field should be applied only to those properties or wells where there are not sufficient data to construct individual or tract production records, or where the productive life so short that a satisfactory individual record can not be obtained."

Jul 1, 1920

By Oliver Bowles

Granites are classed as igneous rocks ; they have been formed by the solidification of rock magmas or solutions from deep within the earth . It is an almost invariable law of nature that magmas which cool quickly form fine- grained or glassy rocks , while those that cool slowly are completely crystallized and are coarser- grained . Granites , being of the latter class , are regarded as having attained their solid form at considerable depth below the surface under conditions of high temperature and pressure . The constituent minerals crystallized out slowly , the crystals interlocking with one another . The great depth of overlying rocks that must have been present when crystallization took place has been removed by erosion over large areas on the surface of the earth , in consequence of which granites appear at or near the surface in many localities . The chief minerals of which granites are formed are feldspars , quartz , and either mica or hornblende . All the essential constituents except mica are as hard as , or harder than steel , therefore granites are difficult rocks to cut and dress . Granites are usually red , pink , or gray , depending on the color of the feldspars . If hornblende or black mica is abundant the rock may be dark green or almost black . Granites are characterized by massive homogeneous texture . They are classified as fine- grained , medium- grained , or coarse - grained . Medium- grained granites are those in which the feldspar crystals average about one- fourth inch in diameter . If relatively coarsegrained crystals appear in a fine -grained ground mass the rock is designated a porphyritic granite . Uniformity in texture and grain size are desirable in building and ornamental stone , although occasionally rocks of variable texture , such as the porphyritic granites , are used . A rock may have the mineral constituents of a granite but show a banded or platy structure due to recrystallization , folding , or other changes while the rock was in a plastic or semimolten condition . Such metamorphic rocks are called granite gneisses . They are used occasionally for building purposes but not as commonly as the uniformly textured granites . - Granites are named from the most abundant mineral other than quartz and feldspar that they contain , being called , for example , biotite granite or hornblende granite . - Commercially other igneous rocks granitoid in texture but more properly classified as syenites , diorites , or gabbros may be classed as granites . Thus the " black granite " of Little Falls , Minn . , is a diorite , and the " black granite " of Eastern Pennsylvania consists of diabase or gabbro . The question is sometimes raised as to the depth to which a granite occurrence may extend . In this respect granites differ notably from limestones , sandstones , or other sedimentary rocks . The sediments were originally laid down in relatively thin beds , and individual formations providing rock of economic value may be quite limited in thickness . Usually the usable beds range between 40 and 200 feet in thickness . On the other hand , granite comes up from below . Its depth is unknown , but in general is very great . It may even be measurable in miles . The reserves of material at depth are to be measured , therefore , by the economic depth of working rather than by the vertical extent of the rock mass . Exceptionally , granites of commercial quality may occur in sills or sheets of limited thickness flanked on either side by rocks of different character , as , for example , at Westerly , R. I.

May 1, 1930

By W. P. Yant, C. E. Traubert

"INTRODUCTION Canister-type gas masks have become an essential part of the equipment of many industries, not only for use in emergencies, but also in performing normal operations of industrial processes and procedures, particularly where ventilation is not practically or economically feasible. They are also used widely for enhancing safety of operations which previous to the development of gas masks had been performed in harmful atmospheres.Since the inception of industrial gas masks the Bureau of Mines has been actively engaged in endeavoring to increase the efficiency and safety of these devices, and this bureau has become a source of advice to manufacturers in producing devices of good quality and to industry in the proper selection and use of these devices. In order to give first-hand information and keep current with the demands and needs of industry it is necessary to perform investi-gations from time to time. This report deals with tests of certain types of commercial gas-mask canisters for protection against mercury vapor.TYPES OF CANISTERS EXAMINEDThis investigation included tests of the following types of canisters:(a) Gas-mask canister filled with 725 c.c. of granular activated charcoal, 8 to 14 mesh, and of a quality used in gas masks which meet the Bureau of Mines approval requirements 4 for protection against organic vapors."

Oct 1, 1932

By E. L. Litchfield

Spark ignition of combustible-gas mixtures is a relatively old subject of investigation and has been treated both experimentally and analytically by many people. Elements of static and current electricity are almost always present in mining and industrial operations, and the spark can be an extremely efficient source of ignition. Thus the practical interest of such problems as the "intrinsic safety" of electrical apparatus is obvious. Ignition and quenching phenomena are the primary laboratory representatives of combustion phenomena that are dynamically nonsteady, and such nonsteady phenomena playa considerable part both in industrial processes and in safety matters, although they are of less immediate practical interest. Considerable effort has been expended by the Federal Bureau of Mines in investigations of spark ignition.5 6 7 8/ Primarily, this work has established the significance of several of the parameters involved. Although the

Jan 1, 1959

By C. A. Komar

Renewed interest in the underground gasification of coal evolves from comprehensive studies of earth fracture systems that indicate that the movement of fluids can be controlled in the coalbed. In particular, directional property studies of natural microfissure occurrence, permeability, ultrasonic velocity, tensile strength, and orientation of intervals of inherent rock weakness, together with geologic structure setting and fracture trace analysis, can predict the gaseous flow paths in the coalbed. Having this information, the dominant direction in which gases generated and/or liberated by heat would move can be determined so that appropriate well patterns can be developed. Together with advances made in drilling technology that permit long horizontal holes to be drilled through the coal seams, tests can be conducted to determine whether directional control will permit devolatilization of the coalbed and gasification of the remaining hot coke in a systematic manner to produce a low-Btu gas suited for the generation of electricity.

Jan 1, 1973

By T. O. Llewellyn

The Bureau of Mines conducted laboratory batch beneficiation tests on a waste granite sludge from New Hampshire to determine the feasibility of recovering a reusable silicon carbide product. The granite sludge responded to attrition scrubbing, desliming, and flotation in either alkaline or acid circuits using fatty acid as a collector. Recovery of over 80 percent of the contained silicon carbide at grades of up to 96 percent SiC was obtained.

Jan 1, 1975

By Donald R. Irving

THIS CHAPTER is new to the Minerals Yearbook and will appear regularly hereafter. Its purpose is to present statistics that reflect technologic trends in the minerals and metals industries (except fuels). Much useful information has been collected annually through the Bureau of Mines mineral commodity and employment and injuries canvasses. However, these data must be supplemented by further data to permit evaluation of the type, direction, and rate of technologic change, which are vitally important in long-term mineral planning. In addition to, and fully as important as, expanding the available data is the need to ascertain that the various items collected are obtained from identical reporting units, to enable direct comparisons to be made.

Jan 1, 1960

By Peter F. Steidl

Seven degasification wells have been completed in the Pittsburgh coalbed at the new Emerald mine near Waynesburg, Pa. Funding was provided by the Bureau of Mines to perform stimulation treatments on five of the wells, to show that this is a feasible and economical means of degasifying part of a coalbed. The seven wells ranged in depth from 590 to 910 feet. Stimulation treatments used 25,260 to 42,660 gallons of foam and 7,400 to 12,800 pounds of 20/40-mesh prop sand. Pumping rates were 10.8 to 11.6 bbl/min and treating pressures were from 1,050 to 1,600 psig. On the day following stimulation, gas production ranged from a few hundred cubic feet per day to more than 100,000 cu ft/day.

Jan 1, 1978

By John P. Conway

This Bureau of Mines investigation was undertaken to determine the feasibility of lock-bolt support in Tertiary-gravel material. Pull tests were performed on five types of rock-bolt anchors to determine their optimum anchorage capacity. Four of these anchors are commercially available; the fifth, an explosive-anchor bolt, was developed by the Bureau of Mines. To increase anchorage capacity, epoxy grout was used with several of the commercial types of bolt. Tests showed that sufficient anchorage could be obtained by employing epoxy-resin grout with the commercially available wedge bolt, or by using the explosive-anchor bolt. Also estimated are bolt spacing and cost of a rock-bolt support system.

Jan 1, 1971

By R. L. Grayson, W. E. Wallace, M. D. Attfield, A. Q. Wearden, P. Bolsaitis, R. D. Kennedy, M. J. Keane, J. C. Harrison

"Respirable high-silica particles from four coal mines. a clay mine and a tunnelling site were analysed for silicon vs aluminum composition by performing scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDS) at electron accelerating voltages of 20 kiloelectron volts (keV). The same particles were analysed at 5 keV to determine possible differences in surface vs bulk composition. In some cases high-silica particles exhibited a decrease in the ratio of silicon to aluminium K-alpha line intensities with decreasing electron beam accelerating voltage. This behaviour is consistent with aluminosilicate surface contamination or occlusion of a silica particle. Some 20 high-silica particles were analysed from each of 10 samples. Powdered aluminosilicate glass was used as a control for the behaviour of silica with a homogeneous distribution of aluminium in the particle. Significant differences were found between the control and sample means for an Illinois bituminous coal mine dust, two western and one central Pennsylvania bituminous coal mine dust low-temperature ashes. and a clay mine and mill dust sample, but not for an anthracite coal mine dust and two central Pennsylvania bituminous coal mine dust low-temperature ashes. INTRODUCTIONRESPIRABLE dust quartz content commonly is measured on bulk samples by using i.r. spectroscopy or X-ray diffraction. For research purposes, individual particle-by particle SEM-EDS analysis at 20-30 keV electron beam accelerating potential may be used also. Such measurements have not provided an unambiguous association of quartz content with occupational pulmonary disease prevalence in exposed workers (WALTON et al., 1977). Rather, there is evidence that coal rank modifies the relationship between dust exposure and pneumoconiosis development (WAL TON et al., 1977; ROBOCK and BAUER, 1990; ATTFIELD and MORRING, in press). SEM-EDS analysis was performed to measure the silicon fraction, Si/(Si +Ai), at 20 and at 5 keV on high-silica particles to determine if some respirable quartz particles generated by mining exhibit heterogenous composition with depth (WALLACE et al., 1990), which might affect the bioavailability of the quartz surface."

Dec 1, 1995

By Joan K. Kuenzi

The purpose of this U.S. Bureau of Mines information circular (Ie) is to discuss how job analysis methods taken from different disciplines can be used together to form a more complete picture of jobs in the mining industry. "Job analysis" is a term used by many researchers, but use of the term is far from standardized. Authors of papers on this subject often state that there is confusion in how or why jobs are to be analyzed, what the resulting information is to be used for, and what the "job analysis" actually means. The process of breaking a job into elemental tasks and analyzing them is used to determine what skills and knowledge are needed to perform a given job, to improve efficiency, and to develop safer job procedures. All are valid reasons to analyze jobs, but the methods used to accomplish the analyses may be very different. In order to create a more complete picture of a job, it may be useful to incorporate methods and information from different areas of study rather than choosing one method for analysis.

Jan 1, 1995

By J. D. Zetterstrom

This report supplements an earlier publication on lightweight aggregates of North and South Dakota.3/ The purpose of the investigation was (1) to study the expansion characteristics of large samples of Dakota clays and shales in a 12-inch by 15-foot rotary kiln; and (2) to improve the laboratory bloating test as a tool for predicting the suitability of samples for the rotary-kiln process. This was done by comparing results of the laboratory and kiln tests.

Jan 1, 1956

By Daryl E. Radcliffe

The Bureau of Mines, as part of an agreement with the Bear Coal Co., Somerset, Col o., evaluated the response of a coal mine roof to time lapse. Time lapse, the interval between exposure and support of the roof, was studied using both instrumentation and statistics. Instrumentation studies were designed to equate displacement and rates of displacement with areas of roof left unsupported from 15 minutes to more than 4 days. A statistical study was completed to compare roof fall occurrence with time lapse intervals encountered during normal room-and-pillar mining. Results from this investigation show time lapse, in the Bear mine, to he insignificant with respect to roof stability after installation of permanent support.

Jan 1, 1980

A significant amount of information regarding the crushed stone and sand and gravel industries in each State is available from State agencies and State trade associations. These organizations continuously monitor the State mineral industries and are therefore an important source of detailed information at the local level. This third edition of the directory was prepared to provide a listing of government agencies and trade associations that can assist the users interested in obtaining detailed listings of crushed stone and sand and gravel producers, in addition to the information published by the U.S. Bureau of Mines.

Jan 1, 1994

By John D. Corrick

The environmental and nutritional characteristics necessary for maximum copper extraction from a low-grade ore by Ferrobacillus ferrooxidans have been explored as have many of the limiting parameters. Criteria considered were oxygen consumption, copper extracted, soluble copper concentration, temperature, pH, particle size, nutrients, and other inorganic salt concentrations. A set of environmental and nutritional conditions were developed for E. ferrooxidans Which supported cell reproduction and maximum microbial oxidation of a low-grade copper sulfide ore. Percolator tests conducted under these optimum conditions resulted in an 18 percent increase in the quantity of copper microbially extracted over that extracted under conditions considered to be standard. Manometric tests determined those extremes of environmental conditions and nutritional factors Which were detrimental to the extraction of copper by E. ferrooxidans.

Jan 1, 1965

Treat contaminated coal mine drainage to meet EPA and State water quality requirements. Approach A model (fig. 1) is presented for selecting, designing, and sizing one or several passive mine drainage treatment systems that can be used in remediation of abandoned mine lands (AML). The three principal types of passive mine drainage technologies for the treatment of coal mine drainage are an aerobic system, a compost wetland, and an anoxic limestone drain. The multistep approach presented here provides a simplified method to characterize the type and magnitude of the water quality problem and then to select either a single treatment system or a combination of treatment systems to address the specific site situation. How It Works Step 1. Discharge Characterization. Characterization of the discharge consists of measuring the discharge flow rate and collecting water samples at the point of discharge for chemical analysis. Both the flow rate and chemistry of a discharge can vary seasonally and in response to storm events. It is important to account for this variability by determining flow rates and water chemistry under various conditions.

Jan 1, 1992