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By Jan M. Mutmansky, Christopher J. Rise

"One of the most serious long term health problems associated with underground,mining is Coal Workers Pneumoconiosis (CWI'), more commonly known as Black Lung Disease. It occurs in some coal workers, normally after 15 or more years of exposure to coal mine dust, and leads to a variety of respiratory problems. Two types of pneumoconiosis are recognized simple CWP, which has been estimated to affect 6.9 percent of miners and is a condition that does not impair the miner's ability to work nor reduce life expectancy; and a more severe form of black lung (called progressive massive fibrosis) that occurs in about one percent of the cases and results in severe lung damage.Although the relationship between coal dust and CWP has long been recognized, detailed knowledge of the relationship is insufficient for setting up authoritative guidelines to reduce the health risks for those employed in dusty,underground environments. CWP is not only a health problem for workers that causes considerable distress, it is also a very expensive problem the total annual costs associated with CWP approach two billion dollars.As part of its efforts to combat CWP, the U.S. Bureau of Mines in 1983 established a Generic Mineral Technology Center to carry out basic research into all aspects of respirable coal dust:— control of dust generation — the behavior of dust in the mine — characterization of dust particles interaction of dust and lung— the relationships among dust generation and mobility and the mine environment, geology, and seam characteristics,Penn State, West Virginia University, the University of Minnesota, and the Massachusetts Institute of Technology are involved in this research, which is administered from the Department of Mineral Engineering at Penn State.Our work is one of the seven projects to be conducted at Penn Slate. We are concerned particularly with the characterization of dust and its relationships with the mine environment, and our main goal is to establish standard procedures for describing and measuring these variables.Coal DustCoal dust is a very complex material that varies greatly in chemical and mineralogical properties. Moreover, it is not the only constituent of respirable dust in the mine. When a coal seam is mined, it is inevitable that rock particles other than coal are included in the material. This rock comes from the mine roof, the floor, and the partings and inclusions within the coal scams. Since the roof and floor strata, the partings and inclusions are often stronger than the coal, mining them frequently causes more dust than mining the coal itself. One of the objectives of our research is to find the relationships between a specific coal's characteristics before it is mined and the respirable dust characteristics after it is mined. We are particularly interested in the size distribution of particles, the chemical properties, and the mineralogical properties."

Jun 1, 1988

By J. A. Organiscak

Enclosed cabs are a primary means of reducing the silica dust exposure of equipment operators at surface mines. The National Institute for Occupational Safety and Health (NIOSH) has investigated various factor effects on enclosed cab air filtration system performance. Factors experimen­tally investigated were intake filter efficiency, intake air leakage, intake filter loading (filter flow resistance), recirculation filter use and wind velocity effects on cab penetra­tion (inside to outside cab concentration ratio). Adding an intake pressurizer fan to the filtration system was also investigated. Results indicate that the intake filter efficiency and recirculation filter were the two most influential factors on cab penetration .Use of a recirculation filter significantly reduced cab penetration over the intake air filter by itself due to the multiplicable filtration of the cab interior air. Cab penetration was also affected to a lesser extent by intake filter loading and air leakage. Adding an intake pressurizer fan notably increased intake airflow and cab pressure while providing only minor changes to cab penetration.

Jan 1, 2008

By M. B. Shirts

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

Jan 1, 1974

By Oliver Bowles

It is noteworthy that 80 to 95 per cent of the gross production of all slate quarries in the United States is discarded as waste . In view of the loss involved in handling so much waste , and the consequent added cost of the finished product , the Bureau of Mines has undertaken a study of the slate industry for the purpose of devising the best means of reducing the proportion of waste , and of utilizing the unavoidable waste . The utilization of waste has received special attention , and the cooperation of many prospective purchasers of waste slate has been enlisted in testing its adaptability for various uses .

Mar 1, 1921

By Joseph Cervik

Gas occurs in coalbeds in an adsorbed and a free gas state, Adsorbed gas is stored in the micropore structure and its transport is governed by Fick's law. The free gas occurs in the. fracture system and flows according to Darcy's law. These two modes of mass transport are interdependent. Production decline curves of coal-gas wells are of the constant percentage decline type and, thus, show no indications of flow characteristics peculiar to coal-gas reservoirs. The effectiveness of surface boreholes as a degasification scheme depends upon both good fracture permeability and a high fracture density. Conventional methods of reservoir engineering analysis are not applicable to coalbeds.

Jan 1, 1969

By C. C. Merrill

Columbium, tantalum, titanium, and zirconium are present in solid waste products generated by the chlorination of rutile used for production of titanium tetrachloride (TiC14). The columbium and tantalum were separated from titanium and zirconium by liquid-liquid extraction techniques using a secondary amine. Salts of these elements are in a leach liquor produced by water leaching of mineral waste from the chlorination of rutile. This waste, produced at the rate of approximately 50,000 tons per year, is about 40 wt pct water soluble. Leach liquors, separated by filtration, were further separated into a solid fraction and a liquid fraction by pressure hydrolysis, The solid fraction containing Cb, Ta, Ti, and Zr was dissolved in HC1-HF and used as a feed solution. Columbium and tantalum were removed from the organic extractant with 1 [N] HC1. A miniature 10-stage reactor showed that the columbium and tantalum present in solution could be separated with a continuous flow.

Jan 1, 1972

By D. B. Dow

The presence of sulphur compounds in petroleum and its products is, generally speaking, undesirable, and the problems involved in removing such compounds are of great importance to the petroleum refiner and to the manufacturer of gasoline. There are several types of these compounds which are dissimilar in physical and chemical characteristics, as evidenced by different objectionable features which they exhibit, and special treatments have been developed to meet conditions existing in various products. This paper deals with the treatment of natural-gas gasoline for the removal of certain sulphur compounds which, if not removed, impart on objectionable odor and in addition badly discolor the product. The presence of this particular type of sulphur compounds is detected by the "doctor" test.* In some instances natural-gas gasoline is purchased on "doctor" test specifications, and the ordinary purchaser, while not buying on "doctor" specifications, is insistent in his demand for a water white product. Gasoline which fails to meet the "doctor" test, if not received by the buyer within a few weeks after time Of manufacture, may be "off color" enough to warrant a deduction from the market price.

Jan 1, 1923

By R. V. Ramani, C. B. Manula, A. Owili-Eger

All the input data required to operate the ventilation simulator except the title, are entered with I10 or F1O.O formats. The title is entered with (18A4) format. The floating points are designated by (FP) and the integers by (INT)

Jan 1, 1975

By J. M. Stuve

Heat of solution measurements of high-purity neodymium metal and neodymium trichloride (NdCls) in 4.360 molal hydrochloric acid (HCI) were used to determine the standard heat of formation (6EPr) of NdCls? From solution data obtained, the heat of formation of NdCls (c) was computed as -248,970 ±260 cal/mole at 298.150 K.

Jan 1, 1965

By T. F. Morse, R. Lundstrom, A. J. Brammer, D. Peterson, M. Cherniack, T. Nilsson, J. D. Meyer, E. Toppila, G. Neely, N. Warren

HAVIC is a collaboration of investigators from North America, Sweden, and Finland having a scientific mandate from NIOSH, to study the exposure response relationship between vibratory tool exposure and adverse health effects. Five cohorts, the Suomossalmi forest workers cohort, Volvo truck cab workers, Connecticut shipyard workers, and matriculating dental hygiene students and experienced dental hygienists have been under study. In the case of shipyard workers, there was survey and tool exposure data from 1988, although detailed subject testing was only available within the timeframe of the study. The truck cab assembly workforce was an inception cohort that had been followed from 1994 along with age-matched controls. The Finnish forest workers had cumulative health data on a cohort (n=52) that had been studied from 1976. For a subset of these subjects, there was detailed tactometry testing in 1990, 1995, and 2003. Accordingly, there was historical as well as new prospective data for the industrial cohorts. The Suomossalmi cohort was reassembled only for our study, which precluded follow-up evaluation and because of retirement is almost certainly the last time this historic group will be studied. The study features are: • Characterization of the exposure response relationship for hand-arm vibration through a study design, incorporating multiple cohorts, some having existing historical data, • Selection of cohorts to include different types of vibration: oscillatory (forest workers) impact (truck cab workers), high frequency (dental hygienists) and mixed (shipyard workers), • Inclusion of two inception cohorts: dental hygiene students and Swedish truck cab workers, • Methods for multi-site and historical integration A description follows. [ ] Methods The study included surveys, physical evaluation, and a selection of battery of “best tests” (cold challenge plethysmography, multi-frequency tactometry, segmental sensory nerve conduction velocity [SNCV]1,2,3) applied across groups to quantify responses to exposure. Exposure monitoring included exposure characterization through daylong data logging at the individual level. Workers at each site were instrumented with a microcomputer-based Vibration Exposure Monitoring (VEM) system, developed at the Biodynamics Laboratory of UCHC and about the size of a police walkie-talkie, to record user-specific tool-operating times, vibrations, and grip forces throughout all, or a representative part, of their workday. More specifically, data logging methods involved the direct monitoring of work cycles, involving tool operation time and measures of tool vibration, namely the root-mean-square (RMS), root-mean-quad (RMQ), and root-mean-oct (RMO), and grip forces, each calculated per minute. For this study, the questionnaire was homogenized with other vibration studies4,5,6. Cross-translation was directed by the multi-lingual investigators, and then reviewed by the study team. To extend comparability with future international studies, questions were also added from the Vibration Network (VINET) draft questionnaire, the product of a European

Jan 6, 2006

By F. W. Smith

This paper is based largely on a study of experimental data obtained by the Bureau of Mines in its comprehensive 25-year survey of the carbonizing properties of American coals. Although the Bureau was interested in and conducted carbonization research-from time to time ever since it was organized in 1910 (1),4/ no systematic studies of the coke-, gas-, and byproduct-making properties of American coals were undertaken until 1927, when the American Gas Association appointed an advisory committee (2) to cooperate with the Bureau in developing equipment and techniques to obtain-data for the accurate assessment of the behavior of coals on carbonization. It was found, in general, that small-scale laboratory tests were unsuitable for the complete evaluation of the coking properties of coal; hence, larger pilot-plant-scale equipment was designed and used (3). It was decided that the scale of the test should be large enough to determine both the yield and quality of the products and yet small enough to maintain adequate control of the process variables (4). These considerations led to development of a carbonizing retort and furnace-of 80 to 200 pounds of coal capacity, suitable for operation at various temperatures up to 1,100° C. (2,0120 F.) and equipment for recovery and measurement of gas and byproducts. This apparatus and the standardized procedure for its operation became known as the Bureau of Mines-American Gas Association (EM-AGA) method or retort (5).

Jan 1, 1955

By Jr. Oitto

A polyester-type resin and deformed-steel reinforcing bars (rebars) were used in to strengthen and to stabilize bolted, fractured wall rock along pas 1:'y. in a western gold mine. Reinforcing bars were placed in boreholes drilled into fractured rock and then were surrounded by resin pumped under pressure into the holes and intersecting fractures until the wall rock was thoroughly impregnated. Pumping and injection equipment and infusion procedures are described. Visual examinations for movement in bonded and adjacent unbonded rock were made for 3 years. Fractured walls containing resin-rebar installations were strengthened. The results suggest that resin-rebar support can be used advantageously and economically in repairing fractured or broken rock when compared with rock bolting or timbering.

Jan 1, 1965

By Helen W. Lang

The Bureau of Mines has developed a very rapid gas chromatographic method for routine determination of oxygen, nitrogen, methane, and carbon dioxide in mine atmosphere samples. Analysis is accomplished in 3 min; readout appears on a single strip chart. The gas sample is split between two columns contained in separate chromatographs. A 5 A molecular sieve column separates oxygen, nitrogen, and methane; a porous polymer column separates carbon dioxide from an air peak. Direct selective analysis of methane from this unresolved air peak is accomplished using a hydrogen flame ionization detector (FID). Carbon dioxide is catalytically converted to methane and detected by FID.

Jan 1, 1972

SMCRA contains five principal regulatory provisions that form the basis for its implementation: Performance Standards Performance standard safe intended to ensure that all surface mining is conducted in a way that protects the environment and the public and ensures that the mined land is restored to productive use following mining. Permits Before developing a surface or underground coal mine, an operator must have a permit issued under SMCRA. An application for a permit to conduct a surface coal mining operation is a detailed document that consists of text and numeric data describing the proposed mining and reclamation. Information must be furnished on pre-mining environmental conditions, existing land use, proposed mining and reclamation, how the performance standards will be met, and the post-mining land use. This provides the regulatory authority with the information necessary to determine that the operation can be conducted in accordance with the regulations. Performance Bonds Before a permit can be granted, an operator must post a performance bond sufficient to cover the cost of reclaiming the site in the event the operator fails to complete reclamation. The bond is not fully released until all performance standards have been met and reclamation of the site has been determined to be successful after five years in the East and Midwest, and after 10 years in the arid West. However, the bond can be partially released as various phases of reclamation are completed. Inspection and Enforcement If a violation of SMCRA or of a state surface mining and reclamation law is observed, an inspector issues a notice of violation to the operator. The violation must be corrected within a specific time, and the operator may also have to pay a fine based on the severity of the violation. If the violation is not corrected, acessation order is issued to immediately stop active coal mining, and the operator must pay a fine. If a violation is especially serious (for example, creates an Following reclamation, the land was immediately put back into agricultural production. Today, grain and corn crop yields have continually exceeded targets. 2 imminent danger to public health or safety or causes significant damage to land, air, or water resources) the inspector immediately issues a cessation order. An operator must correct all violations in order to obtain permits for new mines. Lands Unsuitable For Mining Congress recognized that certain coal deposits cannot be mined without permanent damage to unique cultural or natural resources. As a result, SMCRA protects these resources in two ways: It prohibits mining within the boundaries of national parks, forests, wildlife refuges, trails, wild and scenic rivers, wilderness and recreation areas; in areas which will adversely affect sites listed on the National Register of Historic Places; and within a restricted distance of occupied dwellings, public roads, buildings, parks, schools, churches, and cemeteries; and Provides a process that allows anyone whose interests may be adversely affected by proposed mining to petition to have specific lands designated unsuitable for mining.

Jan 1, 1992

By J. J. Geraghty

U.S. Bureau of Mines researchers investigated the development of an innovative transport system for underground coal mining. A one-half commercial-scale bench model was constructed. Novel magnetic levitation (mag-lev) technology was developed. Frictionless and contact-free transport of a prototype materials container and payload has been demonstrated.

Jan 1, 2010

By R. Hogg

"Some basic features of the science and technology of particle systems are reviewed in the context of agglomeration processes. Emphasis is placed on the force of interaction among particles and with their environment and on their dependence on particle characteristics and interfacial phenomena. The complex role these forces play in the various stages of agglomerate formation, growth, consolidation and structure development, and their influence on final product properties is discussed.INTRODUCTION Agglomeration is an example of a process where the technology has generally preceded the science. Process development• has very often been by trial-and-error albeit with an eye on some basic principles. Nevertheless there is' a scientific basis to the process and a better understanding of the fundamentals can surely lead to improvements in process design and control.Successful processes for the agglomeration of fine particles depend on proper control of the adhesional forces between particles, to encourage agglomerate formation and growth and to provide adequate mechanical strength in the product. At the same time the rheology of the particulate system can be critical to the rearrangement of particles necessary to permit densification of the agglomerate and the development of an agglomerate structure appropriate to the end-use requirements.AGGLOMERATION SYSTEMSUltimately, the performance, of any agglomeration process depends on the• characteristics of the particles and their environment. The specific effects, however, are often complex and may be very difficult to pinpoint by simple observation of the process. A typical agglomeration process involves a number of concurrent or consecutive steps - adhesion, growth, compaction, etc., - each of which is affected by the characteristics of the system, but not necessarily in the same way. The effect of particle size, say on agglomerate growth may be quite different from its effect on compaction and its optimum value may differ widely from one stage to the other. Obviously there.is a general need for compromise in the design and operation, of agglomeration systems. Furtnermore, an understanding of the details of the process and their complexities can be critical to process optimization and improved product quality control."

Jan 1, 1989

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Jan 1, 1997

By B. F. Naylor

"INTRODUCTION Investigation of the physical properties of electrolytic manganese and its alloys has constituted a part of the program of the Bureau of Mines for several years, and already extensive data have been reported. 3-14/ Heat-content measurements above 25° C. of pure manganese 15/ were completed recently at the Pacific Experiment Station of the Bureau, and the results obtained removed many of the inconsistencies in previously reported data. This paper reports heat-content data of seven manganese-copper alloys, varying in composition from 25 to 90 percent man-ganese. The alloys, obtained from the Salt Lake City Station, 16/ had been quenched from 850° C, and cold-worked. Without further heat treatment, heat-content measurements of each of these alloys were made at 100° or less temperature intervals from 450° to 850º C., as it was considered likely that any abnormal behavior of the specific heat would be found in this temperature range. Also, a portion of each alloy was heat-aged at given temperatures for periods of time thought sufficient to reach phase-equilibrium; then the heat-contents above 25° C. were determined at the aging temperatures. (Heat-aging was done at approximately 450°, 550°, 650°, 750°, and 850° C.)METHOD AND MATERIALSThe heat contents were determined by the ""drop"" method in a previously described apparatus. 17/ The calorimeter was cali-brated with electrical energy, measured in international joules, and the results were converted to the conventional thermochemical calorie by the relation, 1 cal. = 4.1833 int. joules."

Jan 1, 1946

By Michael J. Sapko, Eugene M. Bazala, Eric S. Weiss, Kenneth L. Cashdollar

The data presented in this report are the results, to date, of an ongoing Pittsburgh Research Center Disaster5Prevention research program on the explosion hazards associated with blasting operations in noncoal mines. Laboratory and experimental mine tests have shown that oil shale and sulfide ore dusts can be ignited given the proper predispersed dust concentrations, particle size, and kerogen or sulfur content. Methane (CH) gas may also4be present in deep oil shale formations and can pose a significant added hazard to underground blasting operations. The most common explosive used for blasting in oil shale had been ANFO, a combination of ammonium nitrate and fuel oil; blasting in sulfide ore had used ANFO and/or dynamites. Tests conducted at the cannon gallery at Lake Lynn Laboratory near Fair chance, Fayette County, PA, provided a means of evaluating the relative incendivity characteristics of new and existing explosive products. Three explosives—a pumpable emulsion-ANFO blend, a packaged water gel, and an emulsion blasting agent—exhibited low-incendive qualities compared with other more highly incendive products such as ANFO and some dynamites. Based on the data collected during numerous full-scale blasts in oil shale and sulfide ore mines, the low-incendive products significantly reduced or eliminated the ignition hazards while at the same time providing effective fragmentation of the rock. Based on the positive results from the gallery and field testing, low-incendive explosives, coupled with good blasting procedures, show promise in reducing dust and/or gas ignitions associated with blasting operations in oil shale and sulfide ore mining applications.

By Richard L. Jenkins

Systematic sampling, in reconnaissance fashion, of the continental shelves of the United States to define favorable areas of offshore mineral deposits, is one of the long-range marine mineral; programs of the U.S. Department of the Interior. In mid-1966 the Department of the Interior launched its Heavy Metals Program to stimulate domestic output of gold which is in serious short supply. The program is jointly conducted by the Geological Survey and the Bureau of Mines.

Jan 1, 1968