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By A. Stawsky

Effective use of diesel vehicles in underground mining requires attention to improved control of diesel exhaust pollutants such as particulate (soot), oxides of nitrogen and sulfur and carbon monoxide. An experimental survey Is made of diesel emission aftertreatment control techniques including water scrubbers, catalytic converters, exhaust gas recirculation (EGR) and soot filters. Use of two or more techniques in combinations are tested for optimum control of all exhaust pollutants. Dynamometer data is developed for steady state and computer controlled simulated mines duty cycles operation of Deutz F6L-714 and F8L-413 engines. Exhaust Quality indices (EQIs) are calculated from dynamometer data for comparisons among the control combinations examined. The Corning diesel particulate filter (DPF) is shown to be the most promising and practical device. The Corning DPF in combination with EGR provided the best (lowest) EQI from the test data. Use of the DPF requires additional regeneration mechanisms such as a catalytic filter coating or fuel additives. A metal mine field test is made of DPFs on an operational scoop tram to test practical applicability. Further development is proposed for application to various mine conditions and for improvement of DPF regeneration techniques including coating with newly available catalysts.

Jan 1, 1987

By Michael Rieber

In this study a generalized specification and costing model for high tonnage coal carrying conveyor belts of 3.5 to 100 miles is presented. These belt systems, in modular units or flights, of up to 9 miles in length can be considered in terms of gathering systems. The study format is sufficiently open to allow users to insert their own requirements and parameters. A specific case study is provided. Because conveyor belts are feasible almost anywhere, this study has not investigated any specific route or geographic location. Rather, it has concentrated on setting up an heuristic programming model for conveyor belt facility optimization and cost minimization. The analysis starts with the principle factors involved in the design of the system and their optimization for various cases. This is followed, in Section 5.4, with a factor by factor cost analysis based on industry data and the preceding optimization. The next step is the development of both facility and costing models suitable for computer analysis. Logic flow diagrams are presented at each major analytic step.

Jan 1, 1977

The first metal-mine accident-prevention course was prepared and published in 1942-45 as a series of seven miners' circulars (Nos. 51-57). The scope of the course has been broadened, revised, and brought up to date, and it is being published as a similar series of seven miners' circulars (Nos. 51-57, revised) on accident prevention in metal and nonmetallic mines. These circulars are: Accident Statistics (Miners' Circular 51), dealing with general statistics on accidents and injuries at metal and nonmetallic mines, including causes, costs, and the uses of investigations and reports of all accidents.

Jan 1, 1955

By Herbert R. Babitzke

The Minerals Availability System (MAS) was formally established by the Bureau of Mines in May 1975 to provide current appraisals of the engineering and economic availability of nonfuel minerals for consideration in the formulation of both domestic and foreign minerals policy, Domes- tic mineral property reports are developed by the Bureau's four Field Operations Centers, and foreign data are obtained under contract. This site-specific information is subsequently subjected to engineering verification and economic evaluation, and the results are analyzed and published as Minerals Availability System Appraisals. The deposit-specific data are also entered into the computerized MAS data base, where a subset of this information, the Mineral Industry Location System (MILS), is available to the public in the form of computer graphics and listings. Other MAS products are also described. The Bureau's MAS personnel are frequently involved in special engineering and mineral economic projects for other Federal and State agencies. MAS personnel also work closely with the private sector, both in the area of mining and processing cost estimation, and as a source of nonproprietary mineral deposit information.

Jan 1, 1982

By P. M. Sullivan

A physical beneficiation flowsheet was designed by the Bureau of Mines for reclaiming and recycling metal and mineral values contained in municipal incinerator residues, and a continuous processing plant was installed. Residue samples collected from incinerators located in various parts of the country were processed at a rate of 1/2 ton per hour. Continuous screening, shredding, grinding, magnetic separation, and gravity concentration techniques were applied to produce metallic iron concentrates, clean nonferrous metal composites, clean fine glass fractions, and tine carbonaceous ash tailings. Research to develop systems for refining and upgrading the reclaimed metals and glass into marketable products is also underway. From the engineering data developed in the continuous processing plant, evaluations of the capital and operating costs for plants with capacities of 250, 400, 670, and 1,000 tons of dry incinerator residues per day were made. Research on a parallel system to separate and recover the metals, minerals, glass, paper, and plastics from raw, unburned refuse it currently underway, as are studies on the use of air classification to separate the refuse into organic and inorganic fractions.

Jan 1, 1971

By J. A. Pile, Virgil Miller, R. G. Peterson, F. B. Petermann

"INTRODUCTION As virtually no published data are available on the sintering of fine, minus-100-mesh, ferrograde manganese ores, it is most opportune to present data on the amenability of various fine ores and mill products to the sintering process. These data cover the sintering or nodulizing of finely crushed, high-grade pyrolusite and rhodochrosite ores, sintering of manganese carbonate flotation concentrate, sintering or nodulizing the calcine from the deleading of a manganese oxide flotation concentrate, and sintering the calcines made in a Herreshoff furnace from the treatment of manganese sulfate products.If finely sized products are to be smelted in the present electric or blast ferromanganese furnaces, they must be sintered or nodulized. The only specification as to the size of the sintered or nodulized product is that it must pass a 6-inch screen and not contain over 1t-1/2 percent minus 20-mesh material. The minimum-maximum size has not been established. Undoubtedly this opti mum size will be set by the ferromanganese industry when ample quantities of manganese oxide sinters have been smelted."

Mar 1, 1942

By James A. Wasson

Because of the danger to life and property in a coal mine if an oil or natural gas well should be accidentally intersected during mining operations, certain precautionary measures should be carried out prior to entering previously unmined areas. The locations of all wells both at the surface and at the depth of the coalbed should be accurately determined. The condition of the well should be learned from surface observations, and more importantly, from subsurface examination by geophysical logging devices where possible. It is also desirable to learn the physical properties of the hydrocarbon-bearing rock formation and the hydrocarbon fluids. The major hazard presented by oil or natural gas wells to mining operations is that of explosion and fire due to the rapid release of gas into the mine atmosphere. Wellbore pressure, the principal index of danger, should be determined by one or more of the methods described and by a service company such as those listed in the appendix. Because of high pressures involved and the consequent hazard, much emphasis has been placed on underground storage of natural gas in areas containing minable coalbeds. Maps are shown of the principal coal producing areas and the locations of currently active gas storage reservoirs. A checklist has been included of factors to be considered when mining coal in an area where oil or gas wells exist.

Jan 1, 1973

By Raja V. Ramani

The recognition that surface mining need not be viewed as a permanent dedication of the land but rather as a temporary non-renewable use in a series of land uses has caused greater emphasis on the re-use of surface-mined lands. In an effort to develop a procedure for evaluating postmining land use potentials, specific mines in various regions of the U.S. have been studied to determine the extent of current mined-land planning and to discover characteristics that are regional in nature. As part of this investigation, the Indian Head Mine, which is located in Mercer County, North Dakota, has been studied. The Indian Head Mine is presently operated by The North American Coal Corporation -Western Division and has been in operation since 1917 under various ownership. The status of current reclamation and postmining land use planning was reviewed. In addition, the relationship between mine planning and public planning in an area impacted by energy development was investigated. Finally, key factors affecting site potential realization for western surface mines have been identified.

Jan 1, 1983

By Oscar Lee, B. W. Gandrud, F. D. DeVaney

"IntroductionFlue dust which results from the smelting of ores containing appreciable quantities of fines is one of the troublesome products of iron blast-furnace practice. Gases issuing from the furnaces at a high velocity carry small particles of coke, ore and flux into dust-collecting chambers. These particles constitute the flue dust. Lasses of iron ore through the production of flue dust vary between wide limits in the different furnaces, and depend on a number of factors, such as size and design of furnace, amount of fines in the ore, the operating conditions and the blast pressure.Blast-furnace operators of the Birmingham district keenly realize this waste. The ores are comparatively low grade and require more fuel than is ordinarily used elsewhere. Hence the flue dust is low in iron content and high in coke. As a result it is not in suitable condition for direct sintering. In many other iron and steel centers direct sintering is a common practice. In the Birmingham district efforts have been made to prevent this loss by recharging the dust into the furnace, but, as might be expected, a material fine enough to be blown out once will very likely be carried over again.In general, the flue-dust losses in this district will average 250 pounds per ton of pig iron produced, but at times the losses at different furnaces are substantially higher or lower than this figure. On the basis of the present rate of pig-iron production, the annual loss of flue dust exceeds 300,000 tons. The iron content of the dust probably averages 25 per cent, therefore about 75,000 tons of iron is wasted yearly, or about 3 per cent of the iron mined is lost in flue dust."

Jul 1, 1926

By N. L. Wimmler

The Metaline mining district was examined in 1942 by Bureau of Mines engineers with the cooperation of geologists of the Federal Geological Survey. Because the demands of war production were rapidly depleting reserves in some of the older zinc-lead producing districts of the United States, it was decided that an attempt should be made to increase the proved or indicated ore reserves of the Metaline district. With this objective, certain areas to be explored by diamond drilling were selected. The Bureau of Mines began work on this program. January 15, 1943; work terminated September 8, 1945. Forty-five holes were drilled in seven areas, The holes ranged from 154 feet to 2,050 feet in length. Their combined length was 38,150 feet. Thirty-three of the holes were drilled in. the North Pend Oreille and the West Bella May areas.

Jan 1, 1949

The panic bars (and associated linkages and electrical circuitry) that are defined in this document are a machine operator-actuated control for the emergency deenergization of the tram motors on self-propelled, electric and diesel face equipment; including haulage equipment such as shuttle cars. There are nine basic types of panic bars (and several variations) that are recommended in this document, but all of the panic bars arc characteristically of the 'fire door" type that is frequently encountered on outside exit doors of many public, and some commercial buildings. It is also the intent of the following panic bar designs that, when emergency brakes arc added to the face equipment machinery for which they arty required, that they be designed and hooked up so that actuation of the panic bar will result in automatic application of the emergency brakes (immediately following the deenergization of the tram motors). The following panic bar design requirements are a restatement of the proposed requirements defined in the Federal Register, requirements cited in "Guidelines for the Design and Installation of Devices for Deenergization of Self-Propelled Electric Face Equipment/Automatic Emergency Brakes" by C. E. Lester and J. D. Greenhalgh of MESA, and Bendix recommendations that were formulated as a result of discussions with personnel at the various machine manufacturers and underground coal mines that we surveyed, discussions with G. I. Judy (our consultant), etc:

Jan 1, 1974

By W. F. Hazen

This paper describing the mining practices at a 100 per cent mechanized mine working the Pittsburgh or No. 8 coal bed in eastern Ohio is one of a series being prepared by the U. S. Bureau of Mines on mining practices, methods, and costs in the various mining districts of the United States. The purpose of assembling this data is to place before those interested in the mining industry the methods employed and the cost data on the items involved in the winning of the coal and its removal to the railroad car at the tipple. Mining costs are governed by the mining method used, which is selected for its adaptability to local natural physical conditions such as the nature and thickness of the coal, its dip, the character of the roof and floor, and the thickness of the overlying strata.

Jan 1, 1929

By Robert D. Perry

This report describes methods of reclaiming abandoned or inactive tailings ponds and dams. The investigated sites were selected tailings deposits adjacent to metal mines in the southwestern United States and the Pacific Northwest. The basic data developed for each site consisted of the following: a review of existing literature; a site visit that included sampling of the tailings and surrounding materials; laboratory and engineering studies; and development of reclamation plans. Laboratory tests determined the gold and silver content of each tailings deposit and the chemistry of the tailings and surrounding materials. Reclamation plans that include approximate costs were developed for five tailings deposit sites. These ranged in size from 52,000 to 103,000,000 tons. Our conclusions on the remining potential of each site are based on the tailings assay and other technical data. This study concludes that remining as a reclamation tool is feasible at certain sites. Included in this report is a remining program as part of the overall reclamation plan for two sites. Our preliminary results indicate that remining as a reclamation tool is feasible for only one of them.

Jan 1, 1981

By J. T. Matson

This paper describing the mining practice at the Pecos mine of the American Metal Co. of New Mexico, a subsidiary of the American Metal Co., Ltd., is one of a series being prepared by the Bureau of Mines on mining methods, practices, and costs in the various mining districts of the United States. The mine is producing about 18,000 tons per month of zinc-lead-copper ore, chiefly by the square-set and cut-and-fill methods. Costs are given for 1927, 1928, and 1929, the whole producing life of the mine to date.

Jan 1, 1930

By Brian L. Quick

Problem: The National Institute for Occupational Safety and Health's [NIOSH] National Occupational Research Agenda (DHHS Publication No. 96 115) reports that approximately 50% of miners will experience hearing loss by age 50, compared to only 9% of the general population. The present investigation examines three antecedents believed to be associated with miner's use of hearing protection. Method: A posttest delayed posttest control group field research design was employed to assess antecedents toward wearing hearing protection. Results: Following the initial posttest, miners' attitudes and subjective norms were antecedents to intentions to wear hearing protection devices. Also, intentions toward wearing hearing protection predicted hearing protection behaviors. Approximately six weeks later, miners' attitudes and perceived behavioral control were each significant predictors of intentions to wear hearing protection and again, intentions were positively associated with hearing protection behaviors. Impact on Industry: Our results indicate that appeals to normative influences may be the most effective antecedent to employ when persuading coal miners to wear hearing protection. However, messages designed to impact attitudes and perceived behavioral control were also effective.

Jan 1, 2008

By J. J. Forbes

First - aid training is an essential part of safety programs in the mining industry , but it is only a means to an end ; first -aid training will not eliminate accidents , but unquestionably it is of considerable value in any accident prevention program . Numerous features should be incorporated in any efficient , well - developed safety plan ; in addition to first -aid training safety work , to be reasonably effective , should include the establishment and maintenance of a safety organization , safety competitions between mines or sections of mines , safety- inspection committees , accident - investigation committees , safety meetings of mine officials , safety bulletins and posters , employees ' safety publications , Holmes Safety Chapters (which provide for monthly safety meetings of all employees ) , and numerous other activities looking to safe operation of mine or plant . These features are supplementary to the fundamentals of safety-- adequate and effective supervision and discipline . Years of experience , however , have demonstrated that first - aid training is a good accident -prevention auxiliary and should be made an integral part of every company's safety program . Many safety-organization plans have failed because they have been based upon the assumption that the supervisory force should be given full authority and responsibility for achieving safety and eliminating accidents and that the workers , who are most vitally concerned , are nonessential . First -aid training causes the employees to feel that they have a personal and full participation in the safety program and is now available so readily that no individual or organization has any valid excuse for not having it . Early investigations made with a view to bettering health and safety conditions among the employees in the mineral industries demonstrated the need of prompt care of injured employees because , under the difficulties inherent in the occupation , seemingly unimportant wounds , when not treated promptly, became infected and caused permanent disability and even death . Many seriously injured persons , brought out of mines and plants by fellow workers who were ignorant of the approved methods of giving first aid or of safe means of transportation

Aug 1, 1934

By Lathrop E. Roberts

The opinion is general among smelter operators that magnetite formed in the converter and reverberatory furnace has much to do with the loss of copper in the slag. Its action appears to be due in part to its relatively high infusibility, chemical stability, and specific gravity, as a result of Which it tends to form a layer of highly viscous "magnetite mush" between slag and matte. Particles of matte which might otherwise settle out of the slag are unable to pass through this layer. Maier and Van Arsdele have shown that the inclusion of grills of matte in the slag is also at tires very probably due to chemical reaction between magnetite and the constituents of the matte. In smelter control and in any laboratory study of slats the determination of magnetite is therefore a matter of some importance. The difficulties in the ray of making such a determination with any accuracy are rather obvious. Iron may occur in slag as ferric oxide, magnetite, various intermediate oxides, sulphides, silicates, as free metal, and in solid solution of several of these substances. Even if only the total iron content is to be determined, accuracy can be obtained only by painstaking and time-consuming separations from interfering elements. The determination of ferrous, ferric, and free iron in the presence of each other is a difficult matter under the most favorable conditions, and when present in a slag the difficulties are increased by the refractory nature of the sample, by the presence of sulphides, and by such elements as vanadium and molybdenum.

Jan 1, 1931

By Lathrop E. Roberts

[The opinion is general among smelter operators that magnetite formed in the converter and reverberatory furnace has much to do with the loss of copper in the slag. Its action appears to be due in part to its relatively high infusibility, chemical stability, and specific gravity, as a result of which it tends to fern a layer of highly viscous. "magnetite mush" between slag and matte. Particles of matte which might otherwise settle out of the slag are unable to pass through this layer. Maier and, Van Arsdale4 have shorn that the inclusion of prills of matte in the slag is also at times very probably due to chemical reaction between magnetite and the constituents of the matte. In smelter control and in envy laboratory study of slats the determination of magnetite is therefore a matter of some importance. The difficulties in the ray of making such a determination with any accuracy are rather obvious. Iron may occur in slog as ferric oxide, magnetite, various intermediate oxides, sulphides, silicates, as free metal, and in solid solution of several of these substances. Even of only the total iron content is to be determined, accuracy can be obtained only by painstaking and time-consuming separation ions from interfering elements. The determination of ferrous, ferric, and free iron in the presence of each other is a difficult matter under the most favorable conditions, and linen present in a slag the difficulties are increased by the refractory nature of the sample, by the presence of sulphides, and by ouch elements as vanadium and molybdenum.]

Jan 1, 1931

By John Campbell, Miller. W. E., G. W. Jones

"INTRODUCTION Because of its interest in accident prevention, the Federal Bureau of Mines has cooperated with city officials and utilities in investigating the causes of explosions in sewers, manholes, and other underground spaces and has aided in the development of means to prevent such explosions. For several years this Bureau has cooperated with the Boston Edison Co. and the Boston Consolidated Gas Co. of Boston, Mass.,for the purpose of detecting and eliminating combustible and physiologically harmful gases in manholes in Boston and vicinity.These investigations 5/ have shown that combustible gases from the usual sources — leakage from gas—distributing systems and underground tanks and gasoline wastes — can be located and the dangerous conditions remedied by a well—planned, adequately supervised, systematic, and continuous manhole survey. However, other types of gas contamination, termed ""soil"" gases, are present in manholes at times and are more difficult to eliminate because they have no fixed origin and because seasonal and barometric chances affect their production and passage into the manhole. Soil gases usually are abnormally high in carbon dioxide and low in oxygen and contain varying amounts of methane. They are especially dangerous to men entering manholes because they lack sufficient oxygen to support life."

Feb 1, 1940

By R. G. Knickerbocker, David Schlain, F. K. Shelton, J. H. Jacobs

"Many manganese ores contain from 0.1 to several percent cobalt. If such ores arc used for the production of ferromanganese, the cobalt is lost; on the other hand, if they are used for the production of electrolytic manganese, the cobalt can be recovered during the purification of the electrolyte.The production of cobalt in the United States is insignificant compared to the amount consumed, most of which is imported from the Belgian Congo. Cobalt-bearing manganese ores may therefore constitute an important reserve of cobalt in times of emergency. Moreover, the combined value of manganese and cobalt in some ores may be sufficient to warrant the recovery of both metals by the electrolytic manganese process, whereas the recovery of either manganese or cobalt alone might not be economically feasible.In view of the potential importance of manganese ores as a source of cobalt, a survey has boon made of the cobalt content of manganese ores. Most of the data have been obtained from analyses made in the Bureau of Mines, but valuable data have also been obtained from publications of the Geological Survey, various State publications, and other sources. Unfortunately, most published analyses of manganese ores do not include cobalt determinations; when such analyses were fairly detailed, but did not include cobalt, it was presumed that cobalt was not present in significant quantity.Information on the cobalt content of domestic manganese ores is given in table 1. Ores containing 0.1 percent or more cobalt are listed in table 2, and the districts in which such ores occur are shown in figure 1. Most of the known cobalt-bearing manganese ores occur in the southeastern part of the United States. A group of deposits in central Arizona and a few scattered deposits in other States also' contain cobalt."

Apr 1, 1946