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By R. Vernon Helm

Four tables listing values for the various physical properties of those sulfur compounds most likely to occur in petroleum and petroleum products are given herein. The data necessary to bring the first compilation2/ in this subject up to date are given in table I -Revised and Additional Data, which includes boiling points, refractive indices, densities, and freezing points. Tables 11-, III, and IV are published for the first time and include refractive indices for the F, C, and G' lines of hydrogen and the helium D:3 line; surface tensions and viscosities, and refractivity intercepts, specific dispersions, specific refractions, and parachors. The need for information concerning the sulfur compounds in petroleum is becoming-more urgent because of the necessity of refining larger quantities of high-sulfur crude oil to meet the rising demand for petroleum products. For a number of years the Bureau of Mines has been engaged in research to make available more information concerning the properties of the sulfur compounds in petroleum. The petroleum industry has recognized the value of such studies, and as a result the American Petroleum Institute has established Research Project 48A to study sulfur compounds. The investigations under this Project are to be done in Bureau of Mines laboratories as a cooperative project in connection with the work already started.

Jan 1, 1949

By Thomas M. Barczak

The effect of load rate on the load-carrying capabilities of wood cribs is investigated in this Bureau of Mines study. The modulus of deformation (stiffness) of wood crib blocks has been shown to increase with increases in rates of load application, causing larger load reactions for increases in convergence rates. Since wood cribs are tested in the laboratory at convergence rates that are orders of magnitude faster than typically would occur underground, wood cribs tested in the laboratory will react larger loads than the same cribs would react underground for the same displacement. Tests conducted in the Bureau's mine roof simulator on green wood crib blocks indicate that the increase in stiffness for increasing load rates diminishes at displacement rates beyond 0.1 in/min, making crib load nearly independent of load rate for rates faster than 0.1 in/min. Seasoned wood specimens were not as con-sistent in load-rate dependency. Some possible explanations of observed load-rate behavior on wood crib specimens are also postulated in this paper.

Jan 1, 1988

By C. H. Elder

An analysis of the geologic structure of an area of Buchanan County, Va., was made by the Bureau of Mines using imagery from an airborne AN/APQ-97 side-looking radar system to evaluate that mapping technique for delineating structural features that may cause mining problems. Side-looking airborne radar (SLAR) was found to be a useful remote sensing tool for geologic structural analysis, Fault and joint systems identified by lineaments and linear patterns in the imagery were verified by surface and in-mine observations. Little Paw Paw fault was extended 10 miles by SLAR lineament analysis. A 22-mile fault, here named the Bishop-Bradshaw Creek fault, was mapped by lineament analysis and verified by observation of the fault on the Bishop Coal Co. mine map and on offset patterns of commercial gas production along the fault and surface observation of lineament along the fault. Three major super-imposed joint sets and several fault or fractured zones were identified by SLAR lineament analysis, showing more complex structure than earlier mapping indicated. SLAR imagery accurately delineated structural features that are known to affect gas migration and accumulation and that weaken the rock forming the immediate roof to mine workings, causing mining problems and potentially hazardous environment in the mines.

Jan 1, 1974

Objective To identify techniques to reduce the probability of gob gas explosions. Background In the last 6 years, seven explosions of methane and/or coal dust occurred within worked-out, sealed areas (gobs) of underground U.S. coal mines. These explosions, believed to have been started by lightning, destroyed many mine seals and caused much damage external to the sealed area. Three of these gob gas explosions occurred in one mine in Alabama over a 3-year period. Fortunately, the explosion forces and the toxic gases that vented from the sealed gob area did not cause fatalities or injuries, but they destroyed several large seals. If miners had been inspecting or working near these areas, the potential for serious injury and/or death would have been high. The United Mine Workers of America and the Mine Safety and Health Administration (MSHA) requested that the National Institute for Occupational Safety and Health (NIOSH) help identify the mechanisms for lightning penetration into the gob and recommend ways to reduce the probability of occurrence of future explosions from such lightning penetrations into sealed areas of underground coal mines. Because three of the explosions occurred in a single mine, special attention was focused on these particular explosions. The first occurred in April 1994 in a sealed area, which enclosed about 1.35square miles of abandoned workings (gob). This explosion destroyed 3 of the 38 seals that surrounded the gob. These seals were less than 2,000 ft away from three 4.5-in-diam steel-cased test wells that extended from the surface into the mine entry. At the time of the explosion, the National Lightning Detection Network (NLDN)verified 12 lightning strikes within 10 miles of the mine, including several above the gob. After the 1994 explosion, the damaged seals were rebuilt using an acceptable seal design capable of with standing a 20-psi explosion, as required by 30 CFR 75.335. On January 26,1996, a second gob explosion destroyed five more cementitious pumpable seals less than 2,000 ft away from those destroyed in 1994and even closer to the steel-cased wells. The NLDN verified72 lightning strikes in the area of this second gob explosion. Compressive strength analyses of fragments from the destroyed seals showed that strengths ranged from 11 to 138 psi, with an average of83 psi. This is over 100 psi below the minimum 200-psi compressive strength requirement for cementitious pumpable seals. These seals were again replaced. On July 9, 1997, the third and most violent explosion occurred in the same vicinity of the last two explosions. Three more cementitious pumpable seals were destroyed, including one newer seal that exceeded the minimum 200-psi compressive strength requirement. The NLDN verified 695 lightning strikes above the mine during the time in which the explosion occurred. MSHA's

May 1, 2001

By Irving Hartmann

Rock-dusting of coal mines is a most important safety measure for preventing or limiting the propagation of explosions. The Bureau of Mines has recommended for many years that rock dust be distributed on the top, ribs, and floor of mine entries and other workings of all bituminous coal and lignite mines in sufficient quantities to maintain the incombustible content of the dust above the minimum requirements. Rock-dust barriers constitute a secondary safeguard used occasionally to complement generalized rock dusting at entrances to panels and side entries or at other locations. In general, rock dust can be applied effectively with modern rock-dusting machines. However, in thin coal beds, in certain back entries, and in some other areas, rock-dusting machines cannot be used conveniently. Furthermore, many small mines find the purchase of machines costly. In such cases, rock dust is not used at all, or else it is distributed by hand, a relatively slow and costly procedure. In recent years some coal mines have started applying rock dust with the aid of permissible explosives. This may be done in various ways. One method consists in placing a stick of explosive on the floor of a room or entry midway between the ribs and covering the stick with two bags of rock dust that are slit on top and set crosswise one above the other. The explosive is then fired, causing the rock dust to be distributed on the nearby roof, rib, and floor surfaces. The procedure is repeated at desired intervals until the entire area is rock dusted. The method is claimed to be rapid, safe, and inexpensive.

Jan 1, 1950

A new horizontal borehole packer for use in coal beds has been developed. This packer utilizes a principal of operation which has not previously been used. The resulting packer is less costly to purchase, can be easily repaired in the field with inexpensive expendable parts. This report describes the development and testing of the new packer and the evaluation of commercially available packers.

Jan 1, 1971

By W. M. Weigel

"Sand is one of the most useful and, fortunately, one of the most common mineral commodities. By far the largest proportion of the production is used in construction, including all forms of building, concrete and paving, sand for this purpose is produced in every State in appreciable amounts. Excluding send used for railroad ballast, molding sand stands not in tonnage produced, followed by glass sand.Special sands. In addition to the above, many grades of sands, with special characteristics, are used in industrial processes, and may be classed in a group as ""special sends"". This includes filter sand, sand blast sand, engine sand, abrasive send, fire or furnace send, special flooring sand, roofing sand used as a finish for prepared roofings and pottery placing sand sand blast and filter sand have been discussed in previous reports.Very few send companies depend upon the production of any one of these grades, as their source of revenue. They are generally especially prepared from the bank run of sand by different methods of screening or washing, or may, in some instances, be by-products from the production of ether grades. Many companies not now producing them might be able to supply local demands by a slight addition to their plant. In nearly all cases, they command a better price than the usual grades of building sand.Definitions and Properties.Engine sand, or traction sand, as it is sometimes called, is used to prevent the slipping of the driving wheels of locomotives, or other self-propelled vehicles, on wet or slippery rails. Its greatest use is, of course, for railroad locomotives, but street cars use considerable amounts and mine locomotives require its use. As the send must be very dry when used, most consumers have their can drying equipment, so it is often shipped damp, with its natural water content on what resulting from washing by the producer."

Oct 1, 1924

By F. D. Everett

The Burgin shaft of Bear Creek Mining Co. near Eureka, Utah, was sunk during 1956 and 1957 as part of an exploratory program, searching for lead, zinc, copper, silver, and gold ore bodies hidden from the surface by several hundred feet of volcanic rocks. This paper describes the sinking methods and operating practices of Centennial Development Co., contracting firm for Bear Creek Mining Co., in sinking a 3-compartment vertical shaft 1,100 feet. The operation featured the Cryderman positive-action, clam-type shaft mucker. The shaft was completed in 142 days by a shaft crew of 10 men and a top force of 10 men, including supervision.

Jan 1, 1959

By O. C. Blade, Elizabeth Hughes

Conservation in the utilization of any product is always subject to improvement if the composition and properties of the product are known. Petroleum is no exception, and knowledge of the characteristics of crude oils, even when given on the broad basis of routine type analyses has proved useful to chemists, engineers, and geologists in improving pro- duction and utilization of petroleum. For a quarter of a century the Bureau of Mines has sought to provide such information regarding crude oils and has analyzed many samples of petroleum by its standardized rou- tine method. Most of these analyses have been published, sometimes in special compilations, other times in connection with reports of research on petroleum. This report is a finding index for all analyses published up to January 1, 1948. The routine method used for all these analyses is basically the same as that described by Dean, et al.. Briefly, the procedure consists of testing by standard methods, small samples of a crude oil for gravity, sulfur, color, and viscosity, and of distilling a sample of the crude oil by a standardized procedure and determining certain properties in the sep- arated fractions and residuum. Careful records are made during the proce- dure, and the distillation data obtained are used to calculate the approx- imate amounts of products present in the sample such as percents of gas- oline, kerosine, gas oil, and lubricants. The data obtained are recorded on a standard analytical report form. An analysis of a sample of typical midcontinent crude oil is shown in table 1. Compilation of these analyses, sometimes in tabular form and usually for specific geographic areas, are published from time to time. Analyses are often shown in connection with other studies, such as engineering field reports. This bibliography is a compilation of references to 115 publications, which contain analyses of crude oils by the Bureau of Mines. References may be found to analyses of crude oils from the United States, Canada,

Jun 1, 1948

By Wesley T. Holmes

In this final stage of a three-part investigation of the smelting of titania-bearing iron materials, the Bureau of Mines conducted semicontinuous smelting tests in a laboratory electric arc furnace on four concentrates and one are. The objective was to substantiate the significance of liquidus temperature measurements in predicting satisfactory slag compositions in electric furnace smelting of titaniferous magnetites to produce pig iron. Previously obtained liquidus temperature data were used in determining flux requirements. Self-fluxing pellets of either ore or concentrate plus fluxes and reductants were made to produce pig iron and slags containing 0.2 to 0.6 percent titanium. Individual constituents of the slags generally agreed within 5 percent with the value of the corresponding constituent of target composition. Liquidus temperature of furnace slags generally agreed within 50° C of the value obtained from corresponding nominal synthetic slag. The results of the three phases of the investigation may serve as guide-lines for determining flux requirements in smelting a wide variety of titaniferous magnetites and other titania and iron-bearing materials.

Jan 1, 1969

By George R. Ingham

This paper is one of a buries being prepared by the Bureau of Mines on mining methods and costs at various mines in the United States, and is a description of the mining practice at Ajo, Ariz., where the New Cornelia Branch of the Phelps Dodge Corporation mines copper ore from an open pit, and operates a concentrator for the treatment of the ore thus mined. ACKNOWLEDGMENTS The authors wish to express their appreciation to M. Curley, manager of the New Cornelia Branch of the Phelps Dodge Corporation, for his review of this paper and permission to publish it. They also wish to acknowledge the assistance given by W. C. Lawson, assistant engineer, in the preparation of the paper.

Jan 1, 1932

By Tobias W. Goodman, George N. Aul, Joseph Cervik

The Bureau of Mines conducted research to degasify a virgin block of coal in the Beckley Coalbed using long horizontal holes drilled in an array from the bottom of a ventilation air shaft. Eight horizontal holes and an in situ pressure hole were drilled in a radial pattern to depths ranging from 418 to 910 ft (127 to 277 m) and 205 ft (62 m), respectively. The investigation showed the shaft was in a basin saturated with water, which resulted in low gas flows from holes. The in situ pressure at 200 ft (61 m) into the coalbed was 79 psig (544.6 KN/m2). The aver- age gas and water flows for the eight holes were 94,100 ft3/day (2,665 m3/day) and 13 gal/min (49.3 l/min) . After 514 days of degasification, 18.7 million ft3 (0.53 million m3) of gas had been drained. Methane face emissions, which were measured as a section advanced toward the shaft, were reduced about 77 pct, emphasizing the value of drainage by this technique. All holes were grouted before the area around the shaft was mined.

Jan 1, 1982

By Harry K. James

Experimental studies of the physical and explosion characteristics of pure hydrazine nitrate and multicomponent systems containing hydrazine nitrate, supplemented with an extensive Literature survey, are presented. Such proper- ties as melting point, heat of fusion, density, viscosity, surface tension, thermal stability, decomposition process, detonation velocity, impact sensitivity, and TNT equivalence are included.

Jan 1, 1970

By Elmer W. Pehrson

The recent establishment of an official price of 64.64 cents per ounce for silver by the President's order of December 21, 1933, has provoked discussion as to the effects of this move on the various metal-mining industries. To assist those of the mineral industry who are interested in this problem, the Bureau of Mines presents the following analysis of basic statistical data concerning; the relation of the silver price to the value of copper ores mined in the United States. The term "copper ore" as used herein includes all ores in which copper is the most abundant base metal paid for. In 1928, this class of ore contributed 98 percent of the total copper output of the United States.

Jan 1, 1934

By D. R. Tesarik

To ensure the stability ofa tailings pond embankment, the height of the phreatic surface must be kept at or below a safe level. In this investigation, the Bureau of Mines analyzed various horizontal drain designs for tailings embankments to determine their effects on location of the phreatic surface. This report describes the investigation, and it includes 21 dimensionless graphs that can be used to estimate the drain spacing and length dimensions necessary to ensure the stability of embankments of various configurations. Analyses were based on the use of two computer codes, a three-dimensional finite-element code and a two-dimensional finite-difference code. The computer-generated results were compared with results obtained from a laboratory embankment model, other laboratory test results, and piezomet-ric data from two actual tailings embankments. Nearly the same phreatic surface locations were predicted using either of the computer codes. For one of the actual embankments studied, the predicted phreatic surface location was slightly higher than the measured location; for the other, the predicted location closely followed the actual surface trend. Phreatic surfaces of the laboratory model were slightly higher than the code-gener-ated locations, and the differences grew larger as drain length increased or drain spacing decreased.

Jan 1, 1984

By Robert M. Becker

The evaluation of existing rock stresses from measurements of the change in diameter of a borehole that is stress relieved by overcoring has become a common practice, The stress evaluation has been generally based ,on isotropic relations whereas rock in varying degrees is anisotropic. A plane elasticity solution for a circular hole along one axis of an orthotropic medium is adapted for evaluation of in situ stress from borehole deformation measurements. A consistent triaxial testing approach for determining elastic properties of the overcore is also outlined. Comparison of isotropic with anisotropic interpretations of the state of stress show that large errors in evaluation may occur if the anisotropic character of the rock is neglected.

Jan 1, 1967

By William A. Vogely

HIGH ACTIVITY, continuing the substantial recovery from the slump of 1954, characterized the domestic nonfuels-mining industries during 1956 Income generated in producing nonfuel minerals and mineral products3 increased 9 percent over 1955 as compared with a 6-percent increase for all industries. Thus, the 1956 performance of the mineral industries, while not as dramatic as the 27-percent increase obtained in 1955, continued to exceed the gains of the total economy. Other measures of mineral activity strengthen this conclusion. The index of physical volume of mineral production, presented for the first time as an integral part of this review, reflects significant gains in all major sectors during 1956; and, although the overall increase was diminished somewhat by the steel and iron-ore strike in July 1956, the all-mineral index (including fuels) reached a new high.

Jan 1, 1958

By A. Wahab Khair, W. M. Devilder

"This paper presents an analysis of fragment size distribution and characteristics of fracture surface in coal cutting using a rotary coal cutting simulator. Coal cutting by a drum type continuous miner was simulated in the laboratory. A series of tests along both the face and butt cleat direction of coal under different operating and in-situ conditions were performed. In each experiment the cut surface was photographed microscopically and the coal cuttings were collected and sized. Data were used to show how and to what extent various parameters effect size distribution of the coal cutting and how this correlates with the characteristics of the fracture surface. This study resulted in establishing a number of distinct correlations between the size distribution and fracture surface. These correlations were primarily based on the degree of interaction between adjacent bits and the amount of bit-coal interaction taking place on the cutting path. Some of the major results of this study are as follows:Zones of bit-coal interactions proved vital toward understanding the effect the conical bit has on the fragmentation process. This in turn led to the identification of areas which are responsible for the production of fines and generation of respirable dust.The various parameters employed in the coal cutting experiments which showed a strong effect on the coal fragment size distribution were: bit type, bit spacing, depth of cut, in-situ stresses, and cleat orientation. Bit angle and cutting head velocity exhibited the least effect and no correlation was established.From this study it is obvious that the key to achieving efficient coal fragmentation is to limit the degree of bit-coal interaction that takes place throughout the bit path while causing maximum interaction between adjacent bits. Accomplishing this not only increases the percentage of large fragments produced but limits the amount of secondary crushing that takes place in the bit path thus resulting in decreasing fines and consequently, the amount of respirable dust generated.Over 2,000 continuous mining machines (introduced in the 1950's) equipped with conical bits or point attach bits account for well over half of the United States' production from underground coal mines. Today, competition in the coal industry has increased, due mainly to coal market conditions and legal restrictions, thus placing an emphasis upon increasing production, efficiency and health/safety of the workers. Mine operators are always interested in finding the most efficient performance of continuous mining machinery to produce the largest amount of size of coal at the lowest cost. An increase of fine material sent to the cleaning plant can seriously overload the plant to the extent that plant efficiencies deteriorate significantly (1). Also, the difficulty and expense of cleaning very small particles often cannot be done economically and thus, thousands of tons of coal are sent to the refuse pile because of costly or ineffective cleaning facilities. It has been said, ""the efficient extraction of coal or rock implies breakage into a size range that contains a minimum quantity of very small sizes"" (2). All known fragmentation theories concur that more fragmentation requires more energy (3). So, the importance of reducing fines is already evident from an outlook upon efficiency.Now, let's consider another view point., duet generation."

Jun 1, 1988

By R. V. Lundquist, A. E. Morris, E. L. Singleton

This experimental research was performed to determine rate - of - reaction constants on the MnO - C and Mn , C₂ - 3MnO systems at 1,100 ° , 1,150 ° , and 1,185 ° C. Reactions were conducted at atmospheric pressure under controlled flow of purified helium through the furnace chamber . The weight - loss method defined reduction percentages , and reaction products were identified by X- ray methods . The system Mn0 - C followed a linear reaction rate , and experimental results produced an apparent activation energy of 55.8 kcal per mole of Mn0 . The system Mn, C - 3Mn0 followed a parabolic rate of reaction law and yielded an apparent activation energy of 114.4 kcal per mole for the reaction .

Jan 1, 1964

By B. W. Gandrud

In July 1948, the Bureau of Mines, United States Department of the Interior, in cooperation with the University of Alabama and mine operators, published Report of Investigations 4306, "A Combination Cleaning and Dewatering Process for Treating Fine 'Sizes of Coal, Preliminary Report In this report a new process, referred to as kerosene flotation; was described, and results of experimental work with the process Previous to the fall of 1947 were given, The contents of the report. were summarized on pages 19 and 20' as follows: In coal-preparation plants using wet methods of cleaning, the most difficult problem is the cleaning and dewatering of the "fines" from about 10-Mesh to 0. A combination proceed is now under investigation that shows promise of practically and feasibly solving this problem. The process is similar to froth flotation, but a generous quantity of kerosene is used as one of the reagents, and the feed is from approximately 10-mesh to 0 considerably coarser than the usual froth flotation feed. The kerosene and the coarseness of the reed result in a floated product that, under certain circumstances, can be dewatered satisfactorily by a simple process of mechanical squeezing, Squeezing is accomplished by means of an ordinary conveying' Auger-and trough assembly with a section of pipe easing at the outer end of the trough. The bottom of the trough and. casing is fitted with wedge-wire sections to permit escape of the water freed by the squeezing action of the auger. On account of the important role of the kerosene, the process has been referred to in this report as kerosene flotation. Up to now, the investigative work has been divided about evenly between the laboratory and commercial plants. Nearly all of the work has been done on sludges containing the solids from the underflow of dewatering screens. A few runs have been made on 10-mesh to 0: fines from raw coal, but in some of those runs the dewatering mechanism, failed to function.

Jan 1, 1950