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By Oliver Bowles

The use of fire as a source of heat was the first step from primitive existence toward modern civilization, and heat has performed functions of inestimable importance throughout the ensuing ages. The first commercial steam engine invented in 1698 demonstrated that heat was an important source of power, and heat has since become the motivating force for railroad trains and steamboats as well as for machines in multitudes of factories. Aside from its function of supplying power, heat is an agent of vast importance in chemical reactions and engineering processes. Because of the high temperature of steam under pressure, losses by radiation from boilers and pipes become excessive unless the radiating surfaces are covered with insulating materials. Insulation is important also for hot-water pipes and many other types of equipment from which heat may radiate. Radiation losses from heated surfaces increase rapidly

Jan 1, 1943

By James J. Dowd

During and immediately following World War II, the heavy demands for steel required the mining of unusually large quantities of coal for the manufacture of metallurgical coke. The largest demand for metallurgical coke is in the Appalachian region, which comprises central and western Pennsylvania, Maryland, West Virginia, Virginia, eastern Kentucky, Tennessee, and Alabama. This demand is satisfied by coke made from coals within the region; consequently, the reserves of coking coal in this region are being depleted more rapidly than reserves in other coal-producing regions. The supply A' high-quality coking coal during the war was inadequate, and some coke were forced to use inferior coals. The coke produced from these inferior coals adversely affected the rate of production. Another national emergency probably would produce a similar condition, and in the interest of -national security, the Munitions Board of the National Military Establishment requested the Bureau of Mines to evaluate the reserves of coals suitable for the manufacture of metallurgical coke. All bituminous coals in the Appalachian region are coking, and as the coal that produces the better metallurgical coke become depleted, other coal previously considered inferior will be used. The general trend is toward the use of lower-quality coals for metallurgical purposes.

Jan 1, 1950

This project, "Analysis of Men, Materials and Supplies Handling Systems in Underground Metal and Nonmetal Mines" documents the productivity and safety aspects of the existing equipment and systems utilized in transporting personnel and supplies from the surface to the underground production work place. The Present Systems Study (this text -Volume II) documents the productivity and safety of existing men and material movement systems for six representative underground metal and nonmetal mines. Identification of common problem areas was performed using recognized industrial engineering techniques. The back-up data for the industrial engineering analysis of each mine is included as respective appendices (Volume III). A summary of the study background material, six mines' problem areas, comparison of problem areas, problem analysis, and solution recommendations are included as the project final report (Volume I), bound under separate cover.

Jan 1, 1975

By Michael Rieber

This study is an extension of our previous work in the area of coal transportation Its subject is the comparative costing of competing transport erodes. A wide range of costs and aspects of costs are dealt with in terms of engineering - economic analyses of the cost of the components which make up the facility and operating system descriptions of each coal transport mode. The cost comparisons, though analyzed, are not meant to be statements of policy but, rather, an input to decision making. The technical material presented in the succeeding volumes, alone with the earlier work cited above, forms the basis for the analyses. This material may also broaden the general understanding of coal transportation issues and problems. The project is divided into two main sections: (1) lone distance coal transport and (2) gathering and distribution systems. Within each section economic and technological comparisons are made of the available modes. These are used as the basis for comparisons among the modes. Inter-modal compatibility is studied with respect to both mixed trunk line shipment anti with respect to feeder to trunk line and trunk line to distribution systems. The engineering and technological data form the bases for the costing and economic analyses.

Jan 1, 1977

By Charles L. Kimbell

In 1988, the aggregate value of total world international export trade in mineral commodities was estimated at nearly $542 billion in current (1988) dollars, which was about 8.6% above the 1987 level, but still 23.7% below the record high set in 1980. Comparable comprehensive data for 1989 were not available in time for inclusion in this chapter, but 1989 returns for developed market economy countries only were 1 1.8% above those for 1988. These countries accounted for about 50% of the total mineral commodity export trade in 1988. It would be unsound to utilize the overall 11.8% growth rate for mineral commodity export trade for these countries to extrapolate the growth in total world mineral commodity trade because these developed market economy countries account for substantially different shares of the five major mineral commodity groups listed in table 2. Specifically, developed market economy countries in 1988 accounted for 56% of world export of ore, concentrate, and scrap, 74.7% of world exports of iron and steel, 71.7% of world exports of nonferrous metals, and 57.8% of all exports of crude nonmetals, but only 26.6% of world exports of mineral fuels. Moreover, even within each of these groups, the actual product mix included in developed market economy country aggregates differ from that in developing market economy country aggregates and in centrally planned economy country aggregates. Nonetheless, an increase of 9% to 12% in the value of world mineral commodity export trade seems indicated by available returns.

Jan 1, 1992

By Guy E. Dent, Hugo E. Kuehn

"SUMMARYFor making a comparison of magnetic surveys measured from the ground and from the air, Worcester County, Maryland, was chosen as a proving ground. Vertical magnetic intensities were observed on the ground, and total magnetic intensities were observed from the air. A comparison of the two magnetic maps reveals similar large magnetic features, but these are displaced in some instances by distances greater than a mile. Magnetic terrane in the two charts is of the same type but often differs greatly in respective characteristic features.The sacrifices in accuracy that may be expected from the use of different systems of diurnal magnetic corrections on ground observations constitute a part of this report.INTRODUCTIONThe value of magnetic surveys for gaining information concerning the crystalline basement is recognized increasingly. That this topography is often reflected to a major degree in the overlying sediments with certain offsetting is well understood. Even where such sediments are deep, the surface topography of upper formations often reflects this bedrock topography to a certain degree."

May 1, 1947

With a growing concern over mine fires, prevention and suppression are hot topics. NIOSH researchers Michael Trevits, Alex Smith and Edward Thimons discuss their research in the area. The leading causes of US mine fires include flame cutting and, welding operations, frictional heating and ignitions, electrical shorts, mobile equipment malfunctions and spontaneous combustion. From 1990 through 2007, there were 1601 reportable fires that occurred in the US mining industry -an average of 89 fires per year. The fact that mine fires are occurring with alarming regularity reinforces the importance of recognizing and eliminating the potential hazards. These statistics also show the need for improved control and suppression technology to ensure worker health and safety if a mine fire does occur.

Jan 1, 2008

By Ernest F. Burchard, J. R. Thoenen

"INTRODUCTION Technically speaking, bauxite is not a definite mineral but a mixture of several minerals belonging to a group of partly consolidated material known as laterite, which have been formed by surface weathering of rocks.The term bauxite is applied to the ore of aluminum, although a substantial amount is used for other purposes, such as a base in certain chemical industries and in the manufacture of artificial abrasives, refractories, and certain cements. Although bauxite has not been classed as strategic it now appears that the domestic supply may be insufficient for expanded defense requirements.Until recently, domestic production of metallic aluminum has been ample to meet requirements, but estimates of pyramiding future needs of the defense program have caused serious attention to be directed to the self-sufficiency of this country, both as to the supply of the raw material, bauxite, and the metallurgical capacity available to convert the ore to metallic aluminum.At the request of the Secretary of the interior, representatives of the Bureau of Mines and the Geological Survey recently investigated domestic resources of bauxite.A preliminary study of published literature and a field investigation disclosed that"

Nov 1, 1941

By Ellis S. Hertzog

The data published in this retort cover only one phase of a special study of tile physical and chemical properties s of only Alabama coals made by the Bureau of Mines. In addition to determinations of friability, the survey included determinations of grindability, B.t.u. value, and ash-fusion temperature. Assay distillation tests, both for high- and low-temperature carbonization, and proximate and ultimate analyses were made also. However, this preliminary paper is concerned only with the results of friability tests and is issued to expedite the release of this information to the public. The friability, test measures the liability of a coal to break into smaller pieces when subjected to repeated handling, as occurs in the mining, preparation, and transportation operations. Friability depends on many physical characteristics of the coal that vary not only between different seams but also in the same seam. The laboratory methods of determining friability have been developed to give a practical means of estimating degradation of size. So far as is known to the authors, no data on the friability of Alabama coals have ever been published. This caper makes available for the first time fairly comprehensive3 information on this subject. Because the procedure for the tumbler test for determining the friability of coal is relatively new to the coal operators, the authors Lave included a, complete description of it in this report.

Jan 1, 1938

Research 82 highlights significant studies conducted during the past fiscal year at Bureau facilities and offices. Readers who want more information about the projects and studies summarized here can contact the researchers whose names and locations appear with each summary. General information on Bureau of Mines programs is available from the Office of Technical Information, 2401 E Street, NW., Washington, D.C. 20241. A listing of principal officials, a location map of field facilities, and a selected bibliography of publications and patents issued on Bureau developments during the past 3 years are provided.

Jan 1, 1982

By M. Hertzberg

This Bureau of Mines report describes experimental and theoretical studies of diffusion flames in free convection. The cross-coupling between buoyancy-induced flows and the combustion process is explored as it relates to the size, structure, and radiative balance of flames. New data are presented for the size-dependent radiance oscillations of diffusion flames and for the angular distribution of the total radiant intensity from a small methanol pool flame. Both amplitude and frequency of the measured oscillations are compared with theoretical predictions that are based on a new view of the structure of diffusion flames. This new view, which is at variance with the traditional one, assumes uniform reaction in the diffusive mixing zone, and recognizes the significance of the role played by convective buoyancy and its duality in both aiding and impeding flame propagation. Buoyancy quenches propagation at low burning velocities, introducing a real discontinuity in the combustion rate. A "flammable volume" is thus defined as that bound between lean- and rich-limit contours. However, in the flow disturbances generated by combustion waves that consume that volume, buoyancy aids propagation by promoting the convective mixing of a new flammable volume. The measured radiance oscillations are manifestations of these propagation and remixing cycles.

Jan 1, 1978

By Donald P. Schlick

The Federal Coal Mine Health and Safety Act of 1969 requires each mine operator to implement the respirable dust sampling program established by the Secretary of the Interior and the Secretary of Health, Education, and Welfare. This program requires frequent sampling of "high-risk" face workers and periodic sampling of other underground workers. Dust samples are collected by the coal mine operator and weighed at the Bureau's Pittsburgh Field Health Group, and the results are processed by the Bureau's Automatic Data Processing Section located in Denver, Colo. This paper presents the system employed by the Bureau to weigh the dust samples and to process and store the data.

Jan 1, 1971

By Lloyd A. Morley

Previous research conducted for the USBM by Penn State personnel (Grant GO-101729) found that a need existed to physically model a typical a-c/d-c coal mine section electrical system. Its purpose would be to permit preliminary evaluations of electrical problem solutions prior to launching full-scale investigations. Such use can result in greater flexibility than afforded by present computer models. Furthermore, numerous problems, which would be virtually impossible to incorporate in a computer model at this time, are more easily analyzed with physical simulation. The development of this system is now proceeding at the USBM's Bruceton Research Facilities. However, electrical specifications of scaled down components for its construction are required. This project is a result of that need and has been funded as an extension to Grant GO-133077. The following report covers these specifications. Scope of Work To represent a mined a-c/d-r. coal mine section, the typical component specifications must detail at least: a. one a-c continuous miner, b. two a-c or d-c shuttle cars, c. one a-c or d-c roof bolter, d. one a-c section fan, and e. feeder cables. Further, each machine should be portrayed by each of its general

Jan 1, 1974

By Robert E. Hershey

1. This investigation shows that the most important beds in Claiborne County, from the standpoint of present production and reserves, are the Coal Creek and Jellico. Together, they contain 69 percent of the known recoverable reserves in the county. Reserves in five other beds are tabulated in this report; in order of quantity of reserves, they are: Blue Gem, Lower Pioneer, Pewee, Big Mary, and Rex. 2. Known measured and indicated reserves in all beds, based on a minimum thickness of 14 inches and on 1,800 short tons per acre-foot of coal in place, are estimated to be 60 million tons, as of January 1, 1953. Of this total, 55 million tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager to permit making an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.

Jan 1, 1956

By Kenneth H. Johnston

This report describes an in situ combustion project and three waterflood projects in Allen, Anderson, and Wilson Counties, Kansas, that will be visited during the 1964 annual tour of the Kansas-Oklahoma Waterflood Association. Among the unique features of the projects are the movement of heavy crude oil through the reservoir and into the wellbore with energy furnished by burning s portion of the crude oil therein. Another feature is the simultaneous injection of C02 and water, through separate tubing into input wells during early development, to increase injectivity at moderate pressures, Discussion of individual projects includes information on their early history, source and treatment of injection fluids, oil production-decline curves, and the results of water injection on oil production.

Jan 1, 1964

By Maria I. De Rosa

The U.S. Bureau of Mines performed experiments to determine the embedded hydrogen chloride (HCI) and smoke particle characteristics during combustion of polyvinyl chloride (PVC) and chlorinated mine materials for development of a test parameter. The experiments were conducted in an approximately 20-L furnace at set furnace temperatures of 250° and 1,000° C, for a 14-min duration, with an airflow through the furnace of 10 L/min. The variables studied, as a function of time, were hydrogen chloride embedded on smoke particles, hydrogen chloride concentrations in the gas phase, smoke particle average diameter (dg) and particle concentration (no), and product of smoke particle diameter and concentration (dgno). Other variables included carbon monoxide (CO), carbon dioxide (CO2), and oxygen (O2) concentrations; sample mass weight loss; and furnace temperatures. Results show that there is a correlation between embedded hydrogen chloride, hydrogen chloride gas concentrations, and inverse of the smoke particle diameter-concentration product (1/dgno); the higher the hydrogen chloride gas concentrations, the higher the embedded hydrogen chloride, the higher the 1/(dgno) values. These correlations will enable development of a simple test parameter to assess the toxic hazard that these materials pose during fire.

Jan 1, 2010

By D. Randolph Berry

The U.S. Bureau of Mines awarded a contract to Foster-Miller Associates, Inc. (FMA) to provide recommendations on the safest, most practical methods for complying with new regulations requiring that all underground coal miners have a self-contained, self-rescuer (SCSR) -a device capable of supplying, in an emergency, 1 hr of self-contained oxygen (no breathing of mine air). This report develops information and recommendations which could be used during the early stages of nationwide compliance, especially in the areas of inspection, testing, and underground storage of SCSRs. Volume I contains an Executive Summary, Introduction, Definitions, Recommended Guidelines for District Managers and Mine Operators, and a Storage Plan Checklist and Sample Form.

Jan 1, 1981

By Eugene H. Skinner

The 7-mile Flathead Tunnel, located in the central Salish Mountains of northwestern Montana, was constructed between 1966 and 1969, With the contract awarded April 19, 1966, drill and blast tunnel excavation began September 30, 1966, and was completed June 21, 1968, in 488 tunnel-driving days, Peak advance was 66 feet per day. On June 27, 1969, all tunnel concrete lining was completed. Average wall and arch concrete placing rates exceeded 1,700 cubic yards daily, with nearly half of the concrete placed during a severe winter season. Major cost savings in concrete tunnel lining were achieved through a value engineering clause in the contract. Achieving consistent results and high rates of placement in concrete lining ranked equal to ground control in overall tunnel problems. Ground control problems exceeded expectations and were of continual concern throughout excavation, One support collapse in the tunnel and one portal slide condition developed during construction. Critical surface geologic exposures were largely obscured; only a portion could be accurately projected underground, An instrumentation program to gather basic data on rock defamation near the heading face for support purposes was a pioneering effort. The Flathead Tunnel was placed in service on November 7, 1970.

Jan 1, 1974

By V. F. Parry

The object of this report is to present certain pertinent data on the physical and chemical properties of South Arcot lignite and to present the results of several special tests to show how the raw lignite can be upgraded to superior fuels for certain special uses. The Bureau of Mines Branch of Coal Technology laboratories at Denver have advocated the drying and carbonization of all low-rank fuels for special uses and have introduced and developed new techniques for upgrading and refining noncoking coals. Application of these techniques to the South Arcot lignites was the object of the investigation, and this report presents significant data necessary for planning a fuel program based on utilization of dried and carbonized dusts. In general, the South Arcot lignite is similar in chemical properties to the high-moisture lignites found in the United States and has some physical properties similar to Australian brown coals. The samples submitted for test had lost moisture before delivery to the laboratory, and it has been necessary to estimate the analysis of the lignite in place in the mine. Various observations made in India by qualified technicians indicate that the bed moisture content of the entire seam is in the range of 54 to 56 percent. For estimating purposes in this report, the bed moisture content has been taken as 56 percent and the ash content of the fresh coal as 2.5 percent. The average analysis estimated for the as-mined lignite is: [Moisture percent 56.0 Volatile matter do.22.0 Fixed carbon do.19.5 Ash do.2.5 Heating value B.t.u. per lb. 4,890]

Jan 1, 1957

A major highlight of Fiscal Year 1993 is the completion of a new research facility dedicated to the advancement of robotics research and development. This new facility brings to the U.S. Bureau of Mines one of the largest and most unique facilities of its kind in the world. Located at the Bureau's Pittsburgh Research Center, the facility consolidates under one roof, all of the resource requirements of a first class automation and robotics research program. The Mining Robotics Development Center (MRDC) is the result of a major renovation of a large under-utilized warehouse-type structure and brings together the laboratories and offices previously housed in five separate buildings scattered throughout the Pittsburgh Research Center's 238-acre site. This new facility will support the computer-assisted mining research program, a high priority, multi-million dollar program that is expected to have a high impact on the health and safety of miners and coal productivity.

Jan 1, 1993