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Provide mine operators with a quick means of identifying the effect of cutting system changes on relative dustiness at the mine face, by developing an interactive computer program for drum-type coal mining machines. Approach A program which simultaneously evaluates machine parameters, coal seam parameters and mine operator-controlled parameters for their effects on relative dustiness has been developed for use on any minicomputer using BASIC computer language. How it works The interactive computer program allows mine operators to make one or more changes at a time to their cutting system to determine how these changes affect relative dustiness of the face. Using this program, mine operators can find the optimum cutting system configuration to minimize dust using their seam conditions and their equipment specifications. The mining machine variables include: number of vane bits, number of gage bits, number of starts, vane wrap, number of end ring lines, rpm, advance rate, ton/min, percentage of time spent cutting per shift, and airflow.

Jan 1, 1986

Predict the spontaneous combustion potential of a coal, using an expert system computer program. Background Approximately 15% of underground coal mint fires in the United States are attributed to spontaneous combustion. These spontaneous combustion fires frequently occur in worked-out or abandoned areas of a coal mine, This makes the control and extinguishment of the fire difficult and often requires large sections of the mine or even the entire mine to be scaled for long periods of time. A prior knowledge of the self-heating potential of the coal can be useful in preventing spontaneous combustion fires through the use of aggressive monitoring and control measures at existing coal mining operations, and in the planning oh new mines. Many factors can affect the spontaneous combustion process in a mine, including the self-heating potential of the coal, ventilation, geologic factors, and mining conditions and practices. Various test methods have been used to evaluate the relative self-healing potential of coals, including crossing point temperature and adiabatic heating methods, and oxygen adsorption techniques. However, these tests arc usually time-consuming and difficult to conduct, limiting their use to laboratories.

Jan 1, 1992

Develop new technology to encourage domestic processing of automobile catalytic converters for recovering platinum -group metals. Background Automobile catalytic converters are used to convert pollutants in automobile exhaust into water vapor, carbon dioxide, and nitrogen, About 1 million troy ounces of platinum-group metals arc used each year in the. United Slates to manufacture catalytic converters. It has been estimated that about 60 pct of the used catalytic converters arc being collected. Most of these used catalytic converters were not processed in the United States but were exported to Japan or Europe for processing. In 1991, about 250,000 troy ounces of platinum-group metals were recovered from scrap catalytic converters collected in the United States. Each short ton of decanned catalyst may contain 30 troy ounces of platinum-group metals valued at over $15,000. Development of an economic process for the recovery of platinum-group metals that can be operated on a small or large scale may increase, the percentage of catalytic converters collected and encourage domestic processing to recover a platinum-group metal concentrate. This would significantly decrease the dependence of the United States on imports for these critical and strategic metals.

Jan 1, 1992

By Paul T. Allsman

THE THREE words, research, mechanization, and automation are keynote words for mining technology during 1962. Basically interrelated, they not only express the major technologic developments in mining but are the signposts pointing out the road ahead. The process represented by each of these words is evolutionary rather than revolutionary, but developments during the past year indicate a climactical stage has been reached in the process of evolution. Mining research has progressed beyond the stage of academic discussion and is a programed activity within the Federal Government,3 the mining colleges,4 and many of the large mining companies.5 Research was a major agenda item at various national and international mining meetings in 1962. A list of these meetings would include such diverse locales as the Workshop and Symposium on Computers and Computer Applications in Mining and Exploration at the University of Arizona in March; and the 5th Rock Mechanics Symposium at the University of Minnesota, in May; the Rock Mechanics Symposium at McGill University, Montreal, Canada, in September; and the Colloquium XIII, International Society for Rock Mechanics, at Salzburg, Austria, in November.

Jan 1, 1963

By Richard J. Mainiero, Michael J. Sapko, Marcia L. Harris

Since 1988, there have been 17 documented incidents in the United States and Canada in which carbon monoxide (CO) is suspected to have migrated through ground strata into occupied enclosed spaces as a result of proximate trench blasting or surface mine blasting. These incidents resulted in 39 suspected or medically verified carbon monoxide poisonings and one fatality. To better understand the factors contributing to this hazard, the National Institute for Occupational Safety and Health (NIOSH) carried out studies in a 12-foot diameter sphere to identify key factors that may enhance the levels of CO associated with the detonation of several commercial trenching explosives. The gaseous detonation products from emulsions, a watergel, and ANFO blasting agents as well as gelatin dynamite, TNT, and Pentolite boosters were measured in an argon atmosphere and compared with those for the same explosives detonated in air. Test variables included explosive formulation, wrapper, aluminum addition, oxygen balance, and density. Major contributing factors to CO production, under these laboratory test conditions, are presented. The main finding is the high CO production associated with the lack of afterburning in an oxygen poor atmosphere. Fumes measurements are compared with the manufacturer’s reported IME fume class and with the Federal Relative Toxicity Standard 30 CFR Part 15 in order to gain an understanding of the relative toxicity of some explosives used in trench blasting.

Provide an economic alternative to drill-blast excavation with the same ability to excavate openings of varied orientation, shape, and size. Approach Develop an efficient, adaptable, mechanical excavation machine that produces unconfined tensile failure in rock. How It Works A drill-split fragmentation machine that combines a drill and a unique splitter has been developed. The drill and splitter are mounted on a carriage that positions the splitter in a hole immediately after it is made by the drill. The splitter creates force loads that cause the rock to fragment, and the process is repeated for excavation. The unique splitter applies both radial and axial loads to the rock mass, which produces an excavation action comparable to pulling a plug. This excavation action distinguishes the radial-axial splitter from typical demolition splitters, which require a free surface parallel to the axis of the splitter toward which to break rock.

Jan 1, 1989

By R. E. Peterson

The Bureau of Mines has undertaken beneficiation investigations on samples representing large tonnages of oxidized taconites in order to develop and evaluate applicable technologies for producing iron oxide concentrates from these materials. Information derived from the investigations can be used to expand the domestic iron raw-materials base and to establish the impact these taconite deposits may have on future national iron ore requirements. This report describes a process that includes reduction roasting, magnetic separation, and flotation, applied to a western Mesabi Range sample taken near Coleraine, Minn. The sample contained 36.8 pct iron and 46.0 pct silica, and represented 0.5 to 1 billion tons of crude material. An average of 962 lb/hr of oxidized taconite was roasted with 33 lb/hr of lignite in a 35-foot-long rotary kiln. Pulverized lignite and natural gas maintained the kiln operating temperature at 850° C. The roasted taconite was beneficiated by magnetic separation and cationic flotation in a 900-lb/hr pilot plant and yielded a product analyzing 68.1 pct iron and 4.6 pct silica, and containing 82.4 pct of the iron in the kiln feed.

Jan 1, 1981

Determine the extent to which remote-sensing techniques, primarily lineament analysis, can be used to identify geologic structures that may affect the location and migration of subsidence over abandoned underground coal mines in the Colorado Springs, CO, area. Compile data using a geographic information system (GIS) to allow efficient and reproducible comparisons and analyses. Background The basis for evaluating abandoned mine land (AML) sites with remote-sensing techniques comes from past and ongoing Bureau ground control research using remote-sensing data to identify potential hazards caused by geologic structures (faults, joints, etc.) above active underground coal mines. Research showed that lineament (linear feature) analysis of Landsat Multispectral Scanner (MSS) images could indicate locations of fractures and fracture trends that had varying, but significant, impacts on the stability of mine openings. Such geologic structures should be identifiable over abandoned mines as well. If fractures are present, even if they arc not faults, they should represent areas of potential instability over these mines and, therefore, should tend to localize subsidence when it occurs, particularly for deep and moderately deep portions of mines.

Jan 1, 1992

By M. J. Kovalik

The effects of the process variables on the production of chemical coke on a chain grate stoker, a type of traveling grate, were studied. Six bituminous coals, ranging in volatile matter from 16.7 to 43.8 percent, were successfully carbonized, yielding chemical coke with acceptable physical properties. The coke yields were dependent on the volatile-matter content of the coal. The air fuel ratio had the most marked effect on the yield and characteristics of the resultant coke, and the general furnace performance. Results can only be predicted; the actual yield and quality of coke obtained from any given coal can only be determined by actual tests using the optimum processing variables to obtain a coke with minimum volatile-matter content and to retain as much of the fixed carbon in the original coal as possible.

Jan 1, 1967

Provide coal mine shafts/slopes with an optimum coal mine shaft fire and smoke protection system composed of reasonably-priced, reliable hardware. Approach Accident and injury data indicate that a relatively low percentage (5%) of underground coal mine fires occur in shafts or slopes. Nevertheless, shaft or slope fires are extremely serious because they block critical escape routes for miners. That also can happen when combustion products resulting from fires in other mine areas contaminate shahs and slopes. Seeking the optimum configuration for a shaft/slope fire and smoke protection systems, the Bureau of Mines gathered data on the performance of existing fire detection devices and signal telemetry systems In several mines, and analyzed the generic protection needs of the U.S. underground coal mining industry. The optimum system developed by the Bureau provided an adequate number of detectors, a wide area of coverage, and an extensive data acquisition, analysis, display, and storage capability. This system. recommended for fabrication and in-mine testing, consisted of a microcomputer-controlled master panel located in the test mine's slope hoist room, and four remote units. Two of the remote units were placed on the surface atop upcast ventilation shafts, a third was situated underground near the slope bottom, and a fourth was installed at the slope top in intake air.

Jan 1, 1986

"INTRODUCTIONThe information compiled in this volume initially formed the response by the Generic Mineral Technology Center for -Respirable Dust (GTCRD) to a review of its research and technology transfer programs performed in 1990 by the Advisory Committee on Mining and Mineral Resources Research. This review for each mineral technology research center is accomplished, as required of the Bureau of Mines by the House/Senate Joint Conference Committee, through site visitation to the research institutions of the GTCRD and an in-depth questionnaire. The information provided by that questionnaire becomes an important factor in their recommendations concerning future directions of the program.The site visitations took place during January and February 1991 at the Milton S. Hershey Medical Center~ The Pennsylvania State University, West Virginia University, University of Minnesota, and Michigan Technological University, in addition to an in-mine visit conducted at the Loveridge Mine in West Virginia. The questionnaire was prepared and made available to the Advisory Committee and the Research Council for their review at the GTCRD annual project review meeting in Hershey, Pennsylvania, in April 1991.The comprehensive nature of the questionnaire and the scope of the information contained therein make it an excellent retrospective of the Center. Having a clear vision of where the Center has been and knowing where it is now helps to guide it into the future. It is believed that such a detailed view of the Center's facilities and research program will be of value to Center personnel and Advisory Committee members. Each aspect of the questionnaire was examined, answered in detail and documented thoroughly. With the completed questionnaire as a guide, this review of the Center's activities provides an update to Respirable Dust Center Research Program Review 1988, published in 1989 as the seventh of the Generic Mineral Technology Center for Respirable Dust volumes. As does that volume, this review presents the complete General Mineral Technology Center questionnaire, with the GTCRD's expanded responses and supporting documentation appended. An examination of the research program, Center personnel currently active on GMTC projects, the number of graduate degrees granted with GMTC supports GMTC publications, the degree of individual interaction, technology transfer activities, the reference center, GMTC equipment and facilities, and envisioned plans for future research directions provides updated information in these areas. In addition, this year, information has been included to demonstrate the interaction between the Center's goals and its research projects, with thorough consideration of actual research needs as specified by the National Academy of Sciences. This volume serves as a review of the years 1989 through 1990, the sixth and seventh years of the Center's operation."

Jan 1, 1990

By W. C. Phalen

"The Phosphate Rock Market:Indications, in the fertilizer market, point to a prosperous condition, caused chiefly by the growing demand for all classes of fertilizer material in spite of a shortage of supplies. Both of these conditions have been caused by the war. The shortage in phosphate rock is being relieved as production increases, but the supply has not caught up with the demand for this spring's trade, at least. Reports from Florida are to the effect that more than half the necessary quota of laborers are at work. This may not appear to be a very good showing, but even this situation is en¬couraging because there is a larger force now at work than has been the case for some time, and it is steadily, though slowly, increasing. Some of the producing companies are conducting advertising campaigns to get laborers back to the phosphate fields and attractions in the way of better housing and living conditions are being offered.Producers are far more confident about the situation than they were two months ago, and though the shortage will not be met before the end of 1920, theme is a surplus accumulating over what is going out on existing contracts.Quotations are now being offered on all Florida rock excepting land pebble and this, it is expected, will be soon quoted.Quotations on Florida rock per ton are as follows:"

Jan 1, 1920

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

This report was prepared by The Pennsylvania State University under USBM Contract No. G0111808. The contract was initiated under the Coal Mine Health and Safety Program. It was administered under the technical direction of DMRC, with Mr. G. R. Schottler acting as the technical project officer. Mr. J. A. Herickes was the contract administrator for the Bureau of Mines. These applications were developed initially as a part of the instructional material for the course Mng 422, "Mine Ventilation and Air Conditioning" at the Department of Mineral Engineering, The Pennsylvania State University. This ventilation simulator was developed under contract from the Department of Environmental Resources, formerly the Department of Mines and Mineral Industries, Commonwealth of Pennsylvania.

Jan 1, 1975

By A. Wahab Khair

"This paper deals with the description of the capabilities of a unique rotary coal cutting simulator which has been designed and fabricated at West Virginia University. It operates under the simulated mining conditions with in-situ stresses (horizontal and vertical stresses) being applied to a coal block of 18 in. x 15 in . x 6 in located in a suitably designed confining chamber. Cutting drum rotation can be varied from 1 to 40 rpm with the capability of stopping the drum after a predetermined number of rotations. Tests can be performed with four different bit angles, 15, 30, 45 and 60 degrees . A maximum of seven bits could be used in seven different orbits. Various cutting depths up to a maximum of 4 in. is possible.Monitoring devices constitute, Linear Variable Differential Transformers (LVDTs), pressure transducers, cascade Impactors, flow meters, flow controls and drum cutting speed. LVDTs are used to monitor the displacement of the coal block as well as the depth of cut. Pressure transducers are used to monitor the changes in pressure, both due to the thrust and due, to the intermittent cutting nature of the rotary cutting. Flow controls will be used to run the drum at a set rpm between 1 and 40 and to provide a different rate of advance. All the above mentioned devices can be operated and monitored by a fully automated control system. Six-stage cascade impactors are used to determine the mass distribution of dust along the rotation path of the drum. The fracture size, shape and Intensity can be studied by optical microscopy and the dust entrainment by using high speed photography.This equipment will basically be used to study the fracture mechanism in coal, associated with operating and in-situ parameters and further relate It to dust generation and entrainment In underground coal mines."

Jan 1, 1988

By Michael J. Brnich

On November 20, 1968, a massive explosion rocked the underground workings of Mountaineer Coal Co.?s Farmington No. 9 Mine in West Virginia. Of the 99 miners who were working in the mine at the time of the explosion, only 21 survived and escaped the mine. This group included eight who were rescued from the Mahan?s Run air shaft. Nearly 40 years after the event, researchers from the NIOSH Pittsburgh Research Laboratory conducted oral history interviews with two of the eight survivors rescued from the shaft. The Farmington No. 9 Mine disaster ultimately led to passage of the Federal Coal Mine Health and Safety Act of 1969 (amended in 1977).

May 1, 2009

By E. D. Gardner

"The Bureau of Mines receives many inquiries concerning favorable areas in which to prospect for gold, procedure to be followed, equipment required, and allied subjects. This circular has been prepared for use in reply to these inquiries.Interest in gold mining and prospecting for gold remains steady. From time to time many people take to the field to search for new gold deposits. A large percentage of them have had no previous experience in prospecting for lode gold; this paper has been written with the hope that it might assist these newcomers.A majority of the metal mines in the United States have been discovered by qualified prospectors who were searching for valuable minerals at the time. Chance, however, always has played a large part in finding mineral deposits. Some of the discoveries of the past were made by men on other errands, such as rounding up burros or hunting game. Accidental discoveries of ore bodies have been made in building roads and trails and in excavating for mine struc¬tures. Evidence of ore has been brought to the surface by burrowing animals and by ants; gold found in the craws of fowl has led to discoveries of deposits. Important discoveries have been made by men who had no knowledge of rocks or minerals; on the other hand, many ore bodies have been found by experienced prospectors, sometimes after hundreds of untrained men had already passed over the ground.The prospector who carries on his work diligently and intelligently is of course more likely to be rewarded for his efforts than the lazy or unintelligent worker; nevertheless, it is obvious that if valuable deposits are not present at the place being prospected none will be found. Conscientious and painstaking efforts to trace gold to its source usually disclose nothing more valuable than some narrow, unworkable seams; however, many deposits that were developed into profitable mines were found by this method of prospecting. Although some prospectors have made several lucky strikes, many others have spent their working lives searching for gold without finding anything worth while. Probably only one prospector out of several thousand ever finds anything worth developing. Moreover, only 1 out of every 300 or 400 properties developed becomes a profitable mine.Prospecting was begun in the Western States in the fifties as the miners looked for the source of gold found in placers. The search for gold has been continuous since that time; the number of prospectors in the field at any one time, however, has varied greatly. Except in some desert regions, practicallyall of the placer fields now being worked were discovered by old timers; more-over, most of the important gold districts were found by early prospectors. Important discoveries of lode mines, however, have been made from time to time. Most of the area in the mining regions of the West has been searched many times by prospectors, and nearly all of the easily found deposits have been located, but it is reasonable to expect that new gold mines will continue to be found. Most of the future discoveries undoubtedly will be of deposits that do not outcrop. Prospecting for such deposits requires considerable digging.Several important discoveries were made in 1934. One of these, the Rogers-Gentry gold mine at the edge of Antelope Valley in Los Angeles County, Calif., was found by an experienced prospector on an old patented homestead a number of miles from the nearest producing mine. The initial discovery at this mine was an iron-stained, decomposed, silicous limestone outcrop, with no vein structure evident at the surface, near a small, barren quartz outcrop and a water seep. Another discovery, the Silver Queen gold mine, in the same general region and near Mojave, Calif., was found by an experienced miner on an open fraction 400 by 1,400 feet in size between two old properties that were thought to have been worked out years ago. The Silver Queen discovery was made as the result of finding a"

Feb 1, 1950

The following methods should be used to protect miners from the adverse health effects of exposure to respirable coal mine dust and respirable crystalline silica: ? Informing workers about hazards ? Establishing written emergency procedures ? Using engineering controls, work practices, and personal protective equipment (including respiratory protection when dust control equipment is being installed, maintained, or repaired) ? Monitoring exposures ? Conducting medical screening and surveillance ? Encouraging smoking cessation ? Maintaining medical records

Jan 1, 1997

By John C. Edwards, Fred N. Kissell

Experimental work by the Bureau of Mines indicates that when a coalbed is degassed by boreholes, the flow of methane may actually increase with time. This phenomenon appears to be the result of a relative-permeability effect; that is, the coalbed permeability to the gas increases sharply with decreasing water saturation. This report reviews the background of experimental evidence indicating a relative-permeability effect, and presents the results of a computer simulation of two-phase flow in coal.

Jan 1, 1975

By J. Hanslovan, R. H. King

An investigation of the feasibility of shielding low-voltage trailing cables in underground coal mines is described. Both laboratory and under¬ground installation results are presented. The main objective of shielding is to reduce the electrical shock hazard; however, several problems will be encountered by mine operators who install shielded cables. Parameters related to such items as purchasing, splicing, troubleshooting, safety, and reliability are discussed. Some of these problems can be minimized by changes in cable constructions and shuttle-car reeling-device components. Both SH-C and SH-D constructions are considered.

Jan 1, 1979

By Howard E. Parkinson

A brief description is given of various Bureau of Mines research activities that have begun since July 1974 and are not being reported on by others at the Third West Virginia University (WVU) Conference on Coal Mine Electrotechnology. An essential feature of the various projects is that they are pragmatic. The projects are applied research and are carried out both by the Bureau in-house research group and by other research groups through contract research. Projects have been directed toward wired-type communications with a special effort to modify the wired systems so as to be more effectively used. The projects are in three groups: Pager phone systems, trolley line phone systems, and guided-wire wireless communications. Also, a brief sketch is given of research that is essential for further developments in mine communications. From the early results of these various projects, the Bureau has good reason to project that there will be improved performance of existing communication systems and that communications will be extended to other individuals working in areas that are excluded from present mine communication systems.