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By L. G. Marsh

The manufacture of lubricating oils from wax-bearing crude petroleums involves the removal and recovery of the paraffin wax contained in the lubricating distillates. During this process several intermediate products are formed, among them the mixture of waxes and oils known to the refiners as "foots oil." Because of its complex character, foots oil is little understood, and therefore methods of handling it in refineries are often inefficient. The Bureau of Mines is studying the manufacture of lubricating oils, and during the work has investigated the redistillation of foots oil. This report gives in brief the results of the investigation, and recommendations based upon it.

Jan 1, 1926

By T. E. Sterner

A laboratory investigation was conducted to determine the applicability of the thermal oil-recovery method as a means of increasing ultimate oil recovery in the Appalachian region. The primary objective was to establish self-sustained combustion in consolidated and unconsolidated sand test assemblies saturated with various amounts of Pennsylvania Grade crude oil and synthetic brine. Tests using blocks of sandstone were unsuccessful because of sealing problems and fracturing of the rock due to thermal stresses. A combustion wave of about 700° F was propagated through the sand-oil-water packs in the linear tube tests. The high air flux used resulted in high oil consumption and rapid movement of the combustion wave through the tubes. Analytical tests on the sand pack showed that sufficient fuel was deposited during the linear tube experiments for a self-sustained combustion wave.

Jan 1, 1967

By S. H. Ash

"INTRODUCTION Mine fires have occurred since underground mining of minerals began, and they are still occurring. The technical literature is replete with papers relating to mine fires.Means and methods for controlling and extinguishing mine fires and preventing explosions and other accidents require the collection and analyses of samples of the atmospheres surrounding the fire. Such atmos¬pheres are complex mixtures of gases (1, 3, 4, 15, 21, 23).3/SUMMARYExperiences at mine fires (1, 3, 4, 15, 21, 23) have proved conclusively that mine-air analyses furnish the only means of judging what is going on in a mine fire area. Mine-air analyses give evidence of conditions that require immediate protection, govern the order and control the manner in which a fire is fought, show the necessity of bulkheads and establish the places to construct them, indicate whether or not a fire is being controlled or is being extinguished, and govern procedure in sealing and unsealing mine fires.It is commonly believed that danger to life and property from mine-fire atmospheres is greatest in coal mines; this is true only to the degree that the explosion hazard is greater in coal mines than in noncoal mines because of the presence of combustible gases. The problem of gas poisoning is greater in noncoal mines because of the more frequent occurrence of poisonous and innocuous gases, oftentimes the lack of controlled ventilation, and usually greater difficulties in sealing mine-fire areas. Sulfide minerals present a serious hazard in many metal-mine fires when sulfur dioxide is formed. The country rock or ore body itself may contain or be limestone, which may be calcined. Emanations of carbon dioxide are found."

Dec 1, 1950

By D. Cummins

This Information Circular presents a brief history of the lead-acid battery and describes ways to prevent serious injury from battery explosions when servicing and charging lead-acid batteries, particularly in the surface mining industry. The Mining Safety and Health Administration (MSHA), U.S. Consumer Product Safety Commission, battery manufacturers, and the mining industry have all contributed information as well as recommendations for injury-free handling for this report.

Jan 1, 1980

By George J. Conroy

This Bureau of Mines publication describes several fault locators and methods, including time domain reflectometers, a frequency domain reflectometer, tone generators, an infrared method, the Murray loop method, and high-voltage "click" methods. The Bureau of Mines has been conducting research into these methods for several years, to improve mine safety and facilitate production through rapid, safe location of trailing-cable faults. The problems encountered in practical applications are discussed, and schematic diagrams of several instruments fabricated by the Bureau are presented. Since no present single method of locating trailing-cable faults is universally applicable, a kit composed of several of the more promising fault locators is advisable.

Jan 1, 1978

By E. C. Lane

This report on properties of commercial motor fuels is the twelfth in a series made in accordance with a cooperative agreement between the Cooperative Fuel Research (C.F.R.) Committee and the Bureau of Mines of the United States Department of the Interior. The first report contained data on motor gasolines sold during the winter of 1935-36.V The -present report, covering the summer of 1941, presents analytical data for 1,857 samples, representing the products of approximately 135 companies. As in previous surveys, these companies include both large and small suppliers. In addition, the Pacific coast is represented by data averaged by the Pacific Coast Technical Group before being submitted, and these data are published exactly as they were received. Conforming to previous surveys, the data cover three groups of samples -- regular-price, premium-price, and third-grade gasolines -- and each group has been aver aged separately. The number of samples, items, and brands comprising each group, exclusive of those of the Pacific coast, are as follows: Regular price, 1,010 samples, 291 items, and 86 brands; premium price, 577 samples, 263 items, and 78 brands; third-grade gasoline, 270 samples 159 items, and 74 brands. The meanings of these terms as used in the surveys are as follows: Sample: The individual supply of gasoline obtained at the filling station and analyzed in the laboratory.

Jan 1, 1942

By J. W. Walkiewicz

The Bureau of Mines investigated alloys containing mischmetal (MM), cobalt, copper, magnesium, and iron for use in permanent magnets in place of the scarce samarium-cobalt alloys. The magnetic properties of MM-Co, MM-Co-Cu, MM-Co-Cu-Mg, and MM-Co-Cu-Fe-Mg alloys were evaluated. Magnets were fabricated by powder metallurgy consisting of arc-melting the metals, crushing and grinding the resultant alloys, alining and compacting the powder, and sintering the compacts. Magnetic values of MHc = 4.7 kOe, BHc = 4.07 kOe, Br = 6.81 kG, and (BH)max = 10.0 MGOe were obtained with a MM-Co alloy containing 36±0.5 wt-pct MM. By substituting copper and magnesium for part of the cobalt, the values for MHc and BHc were increased to 29.0 kOe and 5.89 kOe, respectively. This intrinsic coercivity value exceeded that of Sm-Co alloy obtained in our laboratory. The addition of iron to MM-Co-Cu-Mg alloys resulted in an increase of Br to 6.90 kG and (BH)max to 10.3 MGOe. Copper and magnesium contents of these alloys were optimized to obtain maximum values of MHc.

Jan 1, 1981

By Paul S. Lewis

The Bureau of Mines hydrogenated coals of different rank that had been irradiated with either x-rays or gamma rays. Lignite, high-volatile A and C bituminous, and low-volatile bituminous coals were exposed to l billion roent¬gens of gamma-ray radiation; specimens of high-volatile A and C bituminous coals from other sources received 6 million roentgens of X-ray radiation. Irradiated and unirradiated control specimens of those coals were hydrogenated in autoclave experiments at (6,000-p.s.i. final pressure and 400° C. with retention times of 15, 30, or 60 minutes depending on the coal rank and catalytic treatment. Comparison of results from irradiated specimens with those from the control experiments showed that the radiation had no beneficial effect on the coal. High-volatile C bituminous coal may have been affected by radiation more than the other coals. One billion roentgens appeared to reduce the amount of coal converted to liquids and gases by about 10 pct., and 6 million roentgens reduced it by about 6 pct. then catalyzed with tin. In all other cases, the conversion of irradiated coal was either reduced by as much as 4 pct. or was essentially the sank as that obtained with unirradiated coal. Irradiation during hydrogenation nay be effective for increasing the reactivity of coal and should be investigated; further work with coals irradiated prier to hydrogenation is not recommended.

Jan 1, 1962

By Frank A. Peters

This description of process evaluation techniques used by the Bureau of Mines for studying proposed processing techniques has been prepared to provide those interested in using these studies with an understanding of the methodology. The methods used for preparing both capital and operating cost estimates are described. Each step in preparing the evaluations is described. Types of equipment costs are shown and factors used in the estimates are defined. Uses of the estimates are suggested and several examples are included. The accuracy of various types of estimates is discussed, along with an explanation of the reason for selecting the type used in the Bureau's process evaluation studies.

Jan 1, 1987

By Frank Pilotte

Proper design characteristics for a seismic system to locate miners during a mine disaster are considered in terms of a total system concept. Field hardware, processing equipment, operating personnel, deployment, training, and supportive R and D are necessary elements of the total system. Each of these elements is discussed and an indication given as to the requirements necessitated by each one. Hardware must be portable, rugged, and fieldworthy. Processing equipment must be simple to operate, expandable for future processing improvements, and ruggedized for field use. A small well-trained team must be available for quick response in times of emergency. Alternative deployment procedures are necessary to allow for a variety of situations including both ground and air delivery. Supportive R and D is used to support training and upgrading of the system.

Jan 1, 1974

By d&apos, Kathleen J. Amico

THIS SUMMARY is shown in volumes I and III of this series on mineral production in the United States (including Alaska and Hawaii), its island possessions, the Canal Zone, and the Commonwealth of Puerto Rico, and on the principal minerals imported into and exported from the United States. For further details on production, see the several commodity and area chapters. A summary table comparing world and U.S. mineral production also is included. [ ]

Jan 1, 1960

By Daryl E. Radcliffe

The Bureau of Mines studied the displacement of the roof in a portion of the Bear coal mine near Somerset, Colo, Horizontal-and vertical-displacement gages were installed in a five-entry section during normal room-and-pillar mining procedures. Monitoring of the roof continued until this section was mined out. Displacement measurements in combination with known time lapses between mining and bolting operations indicate that once support is achieved, the length of unsupported time does not appear to affect long-term roof stability in the mine under investigation.

Jan 1, 1978

By Terry S. Cory

This report covers magnetic field strength measurements vs range and frequency in low-medium coal mines. Both quasi-conductor-free and conductor-proximity areas were investigated. The program covered 5 mines, 4 seams, 6 measurement sets, and 3 geographic areas. The results have been summarized in terms of maximum communication range expected per seam and noise condition. Scatter gain is further explored as a simple measure of energy coupled to conductors.

Jan 6, 1978

By Charles L. Kusik

As part of an effort to establish processes that could be exploited in case of adverse changes in international chromium production and trading patterns, this study was sponsored by the Federal Emergency Management Agency (formerly the Federal Preparedness Agency) through the Bureau of Mines, to experimentally determine the feasibility of recovering chromium from critical scrap metals containing significant quantities of this element. Based on a conceptual pyrometallurgical chromium recovery flowsheet developed at Arthur D. Little, Inc., the experimental program described in this report demonstrated key process steps for the recovery of chromium as ferrochromium in a batch process. The process involves oxidation of chromium into a slag phase, subsequent separation of the slag phase from the remaining metal, followed by reduction of chromium from the slag phase to produce ferrochromium.

Jan 1, 1981

By R. O. Kneisley

Rock mechanics measurements indicate that the present two-bed mine design used at the Big Island trona mine, Green River, Wyo., results in stable workings. Vertical pressure changes in the lower panel pillars and horizontal pressure changes in the lower bed roof and floor indicated negligible upper bed mining influence. Pillar stresses stabilized soon after upper bed mining was completed. Strata movements in the pillar ribs, roof, and floor were also negligible and stabilized soon after completion of upper bed mining. Using tributary area theory, the confined core approach, and studies of model trona pillars it is shown that increased extraction ratio is possible. A program of gradually increased extraction ratio accompanied by simple measurements should result in a mine design that includes both higher recovery and long-term stability.

Jan 1, 1981

By Carlton E. Brown

In 1935 , Brown and Yant / described a microprojector ( microscopic arrangement for projecting images on a screen ) for use in counting and measuring the size of dust particles in Owens - jet dust - counter and simila dry samples of dust collected from the air . In 1938 Brown and others , described a modification of this microprojector that could be used also in counting dust in impinger samples . Microprojectors of this second type have been set up by many mining companies and others and have been made commercially available . Hamly and Pullen5/ described a modification of this microprojector for use in making rapid comparative estimates on konimeter samples and other determinations . This report contains information on still another modification named the "midget microprojector " because of its small size .

Sep 1, 1944

By d&apos, Kathleen J. Amico

THIS SUMMARY is shown in volumes I and III of this series on mineral production in the United States (including Alaska and Hawaii), its island possessions, the Canal Zone, and the Commonwealth of Puerto Rico, and on the principal minerals imported into and exported from the United States. For further details on production, see the several commodity and area chapters. A summary table comparing world and U.S. mineral production also is included. [ ]

Jan 1, 1960

The object of this program was to extend the capabilities of visual paging systems both in size and function. The system developed uses the mine pager phone line for communication, monitoring, and remote control. A central station, using a mini-computer, transmits signals by phase inversion modulation of a 16,384 Hz carrier to as many as 999 remote units. The remote unit addressed returns an echo to indicate that it is functioning and, in the case of monitor units, to convey the monitor data. Magnetically latched display discs, which can be seen from both sides when posted, are used for visual paging. Lists of the addresses of posted pages, unanswered pages, and non-echoing units are prepared by the central station computer. The system was designed to be intrinsically safe and should operate for three months on a 12-volt lantern battery.

Jan 10, 1980

By F. D. Wang

The Bureau of Mines has developed a computer program for evaluating pit slope stability by the finite element stress analysis and limiting equilibrium method. The program includes the finite element method of stress analysis using triangular elements, finite-element model mesh generation, plotting of the model mesh and stress contours, calculation of a factor of safety along a circular or a plane failure surface, and location of a critical circular failure surface. Instructions for preparation of input data, an example problem, and the program listing are presented.

Jan 1, 1972

By R. D. Leitch

Beside many other damaging effects of acid mine drainage, corrosion of pipe lines and pumps frequently adds much to mine operating costs. Not only is it often necessary to install special and relatively costly acid-resistant materials, but even these may require frequent replacements. It is not unusual for ordinary steel pipe to last only a few days in some highly acid waters, while other common materials, though more resistant, frequently last only a few weeks. In the spring of 1935, local PWA authorities offered to assign a number of persons to various problems under the direction of regular employees of the Bureau of Mines. It was believed that at least some simple tests on as many different kinds of acid-resistant pipes as could readily be obtained might produce interesting and valuable information for the mining industry. This paper describes the tests and some results that have since been noted.

Jan 1, 1938