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By A. B. Cecala

It has long been known that ventilation is a cost-effective method to lower respirable dust concentrations in all types of mining applications. The National Institute for Occupational Safety and Health has been working on a number of different research techniques that use ventilation as a critical component to lower respirable dust levels at surface and metal/nonmetal operations in the United States. This article presents five such research efforts. The first research area discusses how improving the ventilation flow patterns in an iron ore mill facility lowered respirable dust concentrations by 31 pct throughout the primary grinding area. The second research area examines how respirable dust levels were lowered at a dimensional stone shop by using air cleaning units suspended from the ceiling. A third area discusses how improvements in ventilation at underground limestone mines lowered respirable dust concentrations. The fourth area examines how improvements in dust filtration and pressurization systems significantly impacted the air quality in enclosed cabs of surface mining equipment. The last area presents a newly developed clothes cleaning technique. This technique uses an air spray manifold to blow dust from a worker?s clothing in an enclosed booth, which confines the dust for capture and removal by a baghouse dust collector. These research areas represent an array of different control technologies to lower respirable dust concentrations. Ventilation is an integral part of these control technologies.

Jan 1, 2006

By Joseph J. Wallace, William H. Tavenner, D. A. Reynolds, John M. Provost, James J. Dowd, R. F. Abemethy

"CONCLUSIONSThe investigation shows that there are 5 coal beds of major importance in Wyoming County from the standpoint of present production - Pocahontas No. 3, No. 2 Gas, Sewell, Beckley, and Eagle - and 5 beds of minor importance - Pocahontas No. 6, Cedar Grove, Winifrede, Douglas, and Chilton. The Pocahontas No. 3 bed contains the largest remaining known reserves.Known measured and indicated reserves in all beds, based on a minimum thick¬ness of 14 inches and on 1,800 tons per acre-foot of coal in place, are estimated at 2,665 million short tons as of January 1, 1951. Of this total, 2,121 million short 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 make 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.Recoverable reserves of coal have been estimated in beds 28 inches and more thick. This thickness is about the minimum now being mined by hand loading onto conveyors in the Appalachian region. The weighted average recovery for all beds in Wyoming County, as determined by this investigation, is 55.0 percent. This percent¬age is based on the total thickness of coal (less partings 3/8 inch or more thick) in the bed rather than on the thickness of the coal mined. The known recoverable reserves are estimated to be 1,167 million tons as of January 1, 1951.4. Since most of the Wyoming coals are medium- and low-volatile bituminous in rank and expand during carbonization in modern ovens, they are blended with high-volatile contracting coals."

Apr 1, 1953

By G. W. Jones

"INTRODUCTION As part of its work in promoting safety, the Bureau of Mines is investigating various means of eliminating or mitigating the explosion hazards of combustible gases encountered in mining and industry. Information has been obtained and a procedure developed whereby the explosibility of many complex gaseous mixtures may be calculated in a rather simple manner without the necessity of performing laborious laboratory experiments. An earlier publication 3/ described the method of determining by calculation the limits of inflammability of gaseous mixtures, including methane, hydrogen, carbon monoxide, nitrogen, carbon dioxide, and oxygen. The information published in the above report permitted calculation of the limits of inflamnability of such gases as are liberated by mine fires, gases from explosives, automobile exhaust gases, gases present after mine explosions, blast-furnace gas, and other gases of similar type.Gases liberated in certain potash mines in the western part of the United States sometimes contain ethane, in addition to the gases named. An investigation was made to obtain data from which the limits of inflammability of such gaseous mixtures could be determined by calculation. 4/Similar data have been Published covering all types of natural gases containing wide ranges of concentration of nitrogen and carbon dioxide.5/"

Dec 1, 1944

Protect mine rescuers from heat-induced stress that drastically cuts their endurance and saps their strength. Approach To prevent exhaustion caused by thermal stress, a rescuer can wear a liquid-cooled hood and vest which absorbs heat, thereby reducing the heat-induced strain on the rescuer's heart and circulatory system. How It Works Liquid coolant is continuously circulated through a self-contained system in which the coolant is chilled by a heat sink on the wearer's belt. The coolant, which is a mixture of alcohol and water, is pumped from the heat sink to bladders inside the hood and vest where it absorbs body heat. After absorbing heat In the hood and vest areas, the coolant returns to the heat sink where it is rechilled by passing through a tube coiled around a steel can containing a block of ice. To adjust the temperature of coolant leaving the heat sink unit, a valve can be operated by the wearer, causing part of the flow to bypass the coil. A small pump and a rechargeable battery are also part of the assembly.

Jan 1, 1979

By Allen S. Smith

Analysis of the helium content of a natural gas presents more than the usual difficulties encountered in applying the thermal-conductivity method because of the relatively small amounts of this inert as present and the wide variation in the other constituents. However, the numerous advantages of this method and its adaptability to Continuously recording and control instruments make it worthy of consideration. A specific application of the method described yields quantitative results only when used with gas mixtures of known qualitative compositions which Vary within predetermined limits. Periodic analyses for the helium content of a producing gas well may be conveniently made by an absorption method, and a continuums analytical method is not necessary for this purpose. Natural gas containing 1.75 to 1.90 percent of helium produced from Government-owned wells is processed in the Amarillo (Texas) Helium Plant of the Bureau of lanes. The helium extracted in the plant is supplied to the Army and Navy, and the processed natural gas is sold to a commercial gas company. As complete recovery of the helium in the raw material is not economically practicable, the processed gas contains 0.1 to 0.3 percent of helium, depending upon conditions of operation. Production is checked against the helium removed from the gas, which before the installation of the thermal-conductivity apparatus was calculated from the analysis of a cumulative sample of the processed gas. As conditions of operation affect the residual helium content to a large extent, a composite sample was an uncertain index of the efficiency of the process.

Jan 1, 1934

U.S. Minerals Coordinating Council Advised. -The Critical Materials Act of 1981, H. R. 4281, introduced on July 27, would create a Council on Critical Materials in the White House Executive Office to oversee Federal materials programs involving $1 billion committed to research by 14 agencies, and to serve as the President's focal point to evaluate materials policy. It was introduced by Congressman Fuqua (D-Fla.) whose Committee on Science and Technology has over-sight over the implementation of P. L. 96-479, the National Materials and Minerals Policy, Research and Development Act of 1980. Bulgaria's Mineral Bank. -Recently Bulgaria established a mineral bank to facilitate receipt of foreign credits for exploiting Bulgaria's mineral raw materials. The bank has wide powers to enter into business arrangements with foreign creditors. Bulgaria's main interest in trading with the West is to import the technology for developing energy and mineral resources.

Jan 1, 1981

By Philip C. Tully

[This bibliography contains 3,655 different citations to technical and scienfic literature on helium and alpha-particles, abstracted by 13 abstract service iblicatlons during 1964. Multiple subject classification increases the total number of entries to more than 5,800. Helium citations are listed by 22 major assifications, alpha-particles by 12]

Jan 1, 1970

By Rudy J. Matetic

Over-exposure to noise remains a widespread and serious health hazard in the U.S. mining industries despite 25 years of regulation. Every day, 80% of the nation’s miners go to work in an environment where the time weighted average (TWA) noise level exceeds 85 dBA and more than 25% of the miners are exposed to a TWA noise level that exceeds 90 dBA, the permissible exposure limit (PEL). Additionally, MSHA coal noise sample data collected from 2000 to 2002 show that 65% of the equipment whose operators exceeded 100% noise dosage comprise only seven different types of machines; auger miners, bulldozers, continuous miners, front end loaders, roof bolters, shuttle cars (electric), and trucks. In addition, the MSHA data indicate that the roof bolter is third among all the equipment and second among equipment in underground coal whose operators exceed 100% dosage. A research program was implemented to: 1) determine, characterize and to measure sound power levels radiated by a roof bolting machine during differing drilling configurations (thrust, rotational speed, penetration rate, etc.) and utilizing differing types of drilling methods in high compressive strength rock media (>20,000 psi). The research approach characterized the sound power level results from laboratory testing and provided the mining industry with empirical data relative to utilizing differing noise control technologies (drilling configurations and types of drilling methods) in reducing sound power level emissions on a roof bolting machine; 2) distinguish and correlate the empirical data into one, statistically valid, equation, in which, provided the mining industry with a tool to predict overall sound power levels of a roof bolting machine given any type of drilling configuration and drilling method utilized in industry; 3) provided the mining industry with several approaches to predict or determine sound pressure levels in an underground coal mine utilizing laboratory test results from a roof bolting machine and 4) described a method for determining an operators’ noise dosage of a roof bolting machine utilizing predicted or determined sound pressure levels.

Jan 1, 2006

By R. A. Cattell

A technologic group such as the Petroleum and Natural Gas Division of the Bureau of Mines, which conducts research on many of the complicated and frequently interrelated problems of extracting crude oil and natural gas from the ground, transporting them to market or to places for subsequent treatment, and manufacturing products, should report progress from time to time. Engineers and others who apply the results obtained by this division are closely associated with its personnel, because may of the problems are attached cooperatively with groups in industry. Some of this cooperation is formal, as exemplified by work now in progress under cooperative agreements with the States of Oklahoma, Kansas, and others, but much of it is informal, prompted by the desire to be mutually helpful in the public interest. Furthermore, the published reports of the Bureau on subjects pertaining to petroleum and natural-gas technology come to the direct attention of a relatively large number of persons, whose interest in results and appreciation of the value of this type of work have caused them to be kept currently informed regarding available data.

Jan 1, 1940

By R. A. Cattell

A technologic group such as the Petroleum and Natural Gas Division of the Bureau f Mines, which conducts research on many of the complicated and frequently interrelated problems f extracting crude oil and natural gas from the ground, transporting them to market or to daces for subsequent treatment, and manufacturing products, should report progress from time to time. Engineers and others who apply the results obtained by this division are closely associated with its personnel, because many of the problems are attached cooperatively with groups in industry. Some of this cooperation is formal, as exemplified by work now in progress under cooperative agreements with the States of Oklahoma, Kansas, and others, but much of it is informal, prompted by the desire to be mutually helpful in the public interest. Furthermore, the published reports of the Bureau on subjects pertaining to petroleum and natural-gas technology come to the direct attention of a relatively large number of persons, whose interest in results and appreciation of the value of this type of work have caused them to be kept currently informed regarding available data.

Jan 1, 1940

By S. P. Kinney

The Department of the Interior has recently investigated the atmospheric conditions in tunnels of the Union Pacific Railroad in Utah and Wyoming , by observations made from the cabs of freight locomotives . This work was conducted by the Bureau of Mines at the request of , and in cooperation with , the Union Pacific Railroad Co .. and was brought about by several accidents to members of engine crews while passing through tunnels , from pollution of the tunnel air by exhaust gases from freight locomotives . The object was to determine the cause of gassing accidents , by examining into composition of the air in locomotive cabs while passing through railroad turmels ; to learn the effect of these conditions on the engine crew; and to provide a means of protection for the men so exposed . Gas samples and temperature readings taken in the cabs of locomotives were used in studying the atmospheric conditions to which the locomotive crews were exposed . The symptoms and the physiologica effects produced in men exposed to the atmospheres encountered were studied . The pulse rates and body temperatures were taken , and the determinations of the carbon monoxide content of the blood were made . Various methods for the prevention of gassing and for the protection of men therefrom were considered and tested , among which were the use of mechanical devices for deflecting the smoke away from the engine cab, and the use of various types of gas masks and breathing apparatus . While this investigation is a part of the safety work of the Bureau of Mines in connection with hazards from atmospheres containing carbon monoxide ( CO ) , the results are of particular value to railroads operating steam locomotives through tunnels , and are also valuable to other industries where atmospheres having poisonous gases or of a high temperature and humidity may be present . The results may be summarized as follows :

Jun 1, 1923

By D. Harrington

"Up to the last 10 or 15 years, responsibility for accidents in mines was generally, though not universally, placed upon the person or persons immediately involved. Present-day thought is rapidly veering toward holding the industry responsible for accidents, with ultimate payment of the bill by the consumer, if financial expenditure should be necessary. While it is undoubtedly correct in principle that responsibility for accidents in and around mines should be shouldered by the employer and while it is probable that as time passes the burden will become even more definitely than now that of the mining companies, on the other hand it is an undeniable fact that large numbers of accidents occur through acts of omission or of commission of some person, very frequently the victim of the accident being the offender.Out of about 3,000 persons killed every rear in our -mines and quarries, nearly half or approximately 1,500 of the fatalities are due to falls of overlying material or of persons, about 500 to haulage, about 350 to fires and explosions, about 125 to explosives, approximately the same number to electricity, and about 300 to various miscellaneous accidents.Generally the accidents from falls involve but one or two persons at a time, and the tendency is now as it always has been to charge the victim or possibly a coworker with the responsibility. Usually this sort of accident occurs at or near a working face (statistics indicate that about 80 per cent of fatalities from falls of roof or rib occur near the face), and as it is Generally agreed that it is the duty of the worker to keep his working place safe, the worker and especially the face worker is given the blame in case of accident."

Apr 1, 1930

By Michael J. Pazuchanics

This report documents the current status of the U.S. Bureau of Mines ongoing investigation of the use of adaptive signal discrimination (ASD) systems to distinguish between cutting coal and cutting rock. Cutting-tool forces and vibrations were measured in the laboratory using both conical bits and roller cutters in a linear-cutting apparatus for several material samples and two cutting directions. A number of ASD systems consisting of one or more signal classifiers were trained and tested to study how data window size, type of signal feature, and combining (polling) of classifier results influence system performance. The results show that ASD system recognition rates can be improved by increasing data window size, removing air-cutting portions from the signal data, overlapping data windows, and combining (fusing) information at various levels of ASD system operation.

Jan 1, 2010

By E. C. Lane

"In a previous paper the Bureau of Mines. 3/ presented in condensed tabular form all analyses of Texas crude oils made by the Bureau up to March 193K. This previous report states;The first Al well in Texas was drilled near Oil Springs, Nacogdoches County, in 1863-67. However, the first oil field of major importance in the State was discovered at Corsicana,Navarro County, in 1895. Since that time the petroleum industry try in the State has spread and grown until today petroleum from Texas is an important commodity in world petroleum markets.Since March 1939 samples of Texas crude oils from many new fields, and some older fields not covered in the previous report, nave been analyzed. Those analyses arc reported in the present paper. The annual production by years from 1896 to 1940, inclusive, taken from the figures in the Bureau of Mines Minerals Yearbook, are given in table 1. Production for 1896-1940, inclusive, totals 6,579,715,000 barrels.Various authors reported upon developments and production in the Texas fields in the Transactions of the American Institute of Mining and Metallurgical Engineers, Petroleum Division, for 1941. 4/"

Apr 1, 1943

By E. R. Cole

One objective of Bureau of Mines recycling research is to devise technology that enables recovery of metals and minerals from wastes. From October 1982 through September 1985, researchers at the Bureau and at the University of Missouri Rolla (contract H0222002) investigated the use of nonferrous flue dust with varying Zn contents (11 to 66 pct) as a source of Zn for electrogalvanizing steel wire. The waste dusts used were from a secondary Cu smelter, a brass smelter, a Pb smelter, and a water treatment plant. The dusts were leached in H2S04, and the leach solutions were treated to make electrolyte for electrogalvanizing steel wire using soluble Zn anodes. Cyclic voltammetry was used in an inno-vative method to evaluate the quality of the electrolytes used for elec-rogalvanizing. After electrogalvanizing, the wire was drawn on a labo-ratory draw bench to simulate industrial practice. Corrosion resistance was measured by a number of electrochemical techniques and by the stan-dard ASTM salt-spray tests. After successful bench-scale tests, the process was demonstrated in an industrial pilot plant. Results indicate that nonferrous flue dusts can be used as a source of Zn for electro-galvanizing if certain impurities are either partially or completely removed from the starting electrolyte.

Jan 1, 1987

By David R. Wilburn

The U.S. Bureau of Mines investigated the resources, costs, capacities, market relationships, and short-and long-term supply of bauxite, alumina, and aluminum. The 45 evaluated mines and deposits in 14 market economy countries (MEC's) have a demonstrated resource of 8.4 billion mt of bauxite and an aluminum content of approximately 2.1 billion mt. Developed world bauxite resources and existing primary aluminum smelting and refining capacity are sufficient to satisfy demand through at least 1995, when additional properties (with higher cost levels) would need to be developed to satisfy future demand levels. It is anticipated that new alumina or aluminum production most likely would occur in developing regions with large bauxite potential, low-cost energy sources, and a close proximity to refining and/or smelting capacity. An increase in aluminum recycling capacity would help meet future demand increases. A series of network model supply analyses was performed for the period 1988 through 2000. Based on announced future production levels and assuming demand grows at the level outlined in the analyses, model results indicate there is sufficient material available to meet demand until 1998, where-upon an aluminum shortfall is projected. Additional analyses investigated the effect of a reduced growth rate of demand and regional production variations in Venezuela on the international aluminum industry.

Jan 1, 1993

By B. R. Mohal, S. Chander

"A new technique to determine wettability of powders is presented in this paper. In this technique the times for immersion of individual particles from air into liquids, defined as imbibition times, are measured. Through the measurements of imbibition times for a large number of particles, it is possible to determine homogeneity/heterogeneity of a powder sample with regard to its wetting behavior. Quartz particles give a very narrow distribution of imbibition times showing a homogeneous wetting surface whereas coal particles give a broad distribution indicative of the heterogeneous nature of its surface. The imbibition time measurement technique is considered to have certain advantages over other methods to determine wettability of powders in surfactant solutions. In this study we have also compared the imbibition times with the wetting rate mea¬surements obtained by a modified Walker test.INTRODUCTIONSeveral methods are available for determining wetting characteristics of sol¬ids. Each of the methods has been used in the past to obtain very valuable information for comparing wetting behavior of various solids in a given liquid or for comparing the wetting behavior of several liquids for a given solid. Each method measures a somewhat different aspect of wetting and therefore quantitative correlations between techniques have been difficult. A general approach is to use a method in which close similarity between the technique and the application (where results of wetting measurements are to be used) can be maintained. The objective of this investigation was to develop a method which could be used to determine the wetting characteristics of single particles in surfactant solutions. Wetting of individual particles is of importance in cap¬ture of dust particles by sprays of surfactant solutions.METHODS FOR DETERMINING WETTING — A BRIEF REVIEWThe various methods available for measuring wetting characteristics of solids include: contact angle, immersion/sink time, bubble pick-up, induction time, capillary rise, and displacement method measurements. Some of the methods are briefly reviewed in the paragraphs that follow."

Mar 1, 1989

By J. R. Long

The investigations described herein are concerned with a portion of a systematic research, by the Federal Bureau of Mines on ductile titanium. The Bureau's work on the metal has resulted in development of a semi commercial process for the preparation of titanium and has also made available significant information on the fabrication and physical properties of this new strong, light, corrosion-resistant metal. Considerable interest has been aroused by this work, and a number of other laboratories have begun similar investigations. However, the necessity for Consolidating titanium by normal powder metallurgy methods presents difficulties in producing commercial forms and shapes on a large scale. This investigation was therefore undertaken for the purpose of improving the technique for consolidation of titanium powder into solid nonporous metal.

Jan 1, 1949

By Chas. F. Jackson

The annual reports of the supervising engineers of the nine sections comprising the Mining Division are assembled here and constitute the annual report of the division. In planning activities the aim is to adapt them to changes in conditions, in the needs of the mining industries, and in the public interest; those that contribute most to solving the present problems are emphasized, investigations of less immediate importance being recessed if necessary. The strategic minerals investigations of the bureau afford an example of this change in emphasis to problems of immediate and urgent interest, and during 1941 they comprised, upon the basis of appropriations and expenditures, more than 90 percent of the work of the division.

Jan 1, 1941

The annual reports of the supervising engineers of the nine sections comprising the Mining Division are assembled here and constitute the annual report of the division. In planning activities the aim is to adapt them to changes in conditions, in the needs of the mining industries, and in the public interest: those that contribute most to solving the present problems are emphasized, investigations of less immediate importance being recessed if necessary.

Jan 1, 1941